What does the Bible say about strength?
Isaiah 40:28-31
28 Do you not know? Have you not heard? The LORD is the everlasting God, the Creator of the ends of the earth. He will not grow tired or weary, and his understanding no one can fathom.
29 He gives strength to the weary and increases the power of the weak.
30 Even youths grow tired and weary, and young men stumble and fall;
31 but those who hope in the LORD will renew their strength. They will soar on wings like eagles; they will run and not grow weary, they will walk and not be faint.
New International Version (NIV)
The answer
The Bible teaches that true strength comes from God, not from human self-sufficiency. Physical energy and human resolve eventually fail, but God strengthens His people to endure hardship, remain faithful, and stand against evil.
God gives strength to the weak
God Himself never grows exhausted: Isaiah 40:28 says He “doesn’t faint” and “isn’t weary.” The very next verse declares, “He gives power to the weak. He increases the strength of him who has no might” (Isaiah 40:29). Strength is therefore something God supplies, not something people must manufacture through sheer willpower.
This remains true when the whole person feels depleted: “My flesh and my heart fails, but God is the strength of my heart and my portion forever” (Psalm 73:26).
Waiting on the Lord brings renewed strength
Even the strongest human beings have limits: “Even the youths faint and get weary, and the young men utterly fall” (Isaiah 40:30). In contrast:
“But those who wait for Yahweh will renew their strength. They will mount up with wings like eagles. They will run, and not be weary. They will walk, and not faint.” (Isaiah 40:31)
The promise belongs to those who wait for the Lord, looking to Him rather than trusting in their own fading resources.
God’s power can be displayed through continuing weakness
Strength does not always mean that God immediately removes the hardship. Paul pleaded for his “thorn in the flesh” to depart, but the Lord answered, “My grace is sufficient for you, for my power is made perfect in weakness” (2 Corinthians 12:8-9). Paul therefore concluded, “For when I am weak, then am I strong” (2 Corinthians 12:10).
Weakness is not proof that God has abandoned someone. It can become the place where Christ’s sustaining power is most clearly seen.
Christ strengthens believers for every circumstance
Philippians 4:13 says, “I can do all things through Christ who strengthens me.” In its context, this is not a promise of success in every personal ambition. Paul has just described learning contentment in hunger and abundance, need and plenty (Philippians 4:11-12). Christ gives strength to remain content and faithful in every circumstance, whether comfortable or painful.
Spiritual strength means standing firm
Ephesians 6:10 commands, “Be strong in the Lord and in the strength of his might.” That strength is exercised by putting on God’s armor and standing against the devil’s schemes, because the struggle is spiritual rather than merely human (Ephesians 6:11-13). Biblical strength is therefore not simply feeling powerful; it is depending on the Lord and continuing to stand firm.
Answered from Scripture · reviewed November 11, 2026
Scripture reveals that genuine strength does not originate in human willpower, bodily vitality, or worldly status, but exclusively in the living God. While human ability inevitably exhausts itself and fails, the Lord possesses infinite, untiring power that He freely imparts to the weary who trust Him. Walking through the testimony of Scripture shows that divine strength is made perfect in weakness and sustained through active, faithful reliance on Christ.
The Creator's Might
God Alone Possesses Infinite, Untiring Power
Do you not know? Have you not heard? The LORD is the everlasting God, the Creator of the ends of the earth. He will not grow tired or weary, and his understanding no one can fathom.
Isaiah 40:28 (NIV)
It declares that the everlasting Creator never faints or grows weary, grounding all strength in His unsearchable nature.
The prophet Isaiah anchors every doctrine of true power in the nature of God Himself. In Isaiah 40:28, Scripture asks, "Have you not known? Have you not heard? The Lord is the everlasting God, the Creator of the ends of the earth. He does not faint or grow weary; his understanding is unsearchable." Human stamina burns out because creaturely vitality is limited, but Yahweh draws from no external reservoir; He is Himself the fountain of life. Earlier in Isaiah 40:21, the text presses home that this reality was visible from the foundations of the world. Because God made all things, all authority resides natively within Him. The psalmist mirrors this truth in Psalms 147:5, praising the Lord whose understanding is beyond measure and whose power is vast.
Because God's nature is steadfast, His power never wavers or compromises. Samuel identified Him as "the Strength of Israel," the one who does not lie or change His mind (1 Samuel 15:29). Paul breaks into doxology before this eternal supremacy, proclaiming God the King eternal, immortal, and invisible (1 Timothy 1:17). Man cannot interrogate or counsel this majestic power; as Paul asks in Romans 11:33 and Romans 11:34, who has known the mind of the Lord, whose ways are inscrutable? In the ancient reflections of Job 37:23, the Almighty is exalted beyond human grasp, utterly just and sovereign.
Scripture insists that all power belongs exclusively to God. David writes in Psalms 62:11 that God spoke once, and twice it was heard that power belongs to Him alone. When the prophet Jeremiah looked upon the sprawling cosmos, he confessed in Jeremiah 32:17 that the Lord created the heavens and the earth by His outstretched arm, meaning nothing is too hard for Him. King David sums up this theology before the assembly in 1 Chronicles 29:11, attributing to the Lord all greatness, victory, and majesty in heaven and on earth.
| Passage | What it says |
|---|---|
| Isaiah 40:21 | Asks whether Israel has not understood from the earth's foundations that God is sovereign over all created things. |
| Isaiah 40:28 | Affirms that Yahweh, the Creator of the ends of the earth, neither faints nor tires, and His understanding is beyond searching. |
| Psalms 147:5 | Proclaims that our Lord is great and abundant in power, possessing infinite understanding. |
| 1 Samuel 15:29 | Names God as the Strength of Israel who does not lie or change His mind. |
| 1 Timothy 1:17 | Ascribes eternal honour and glory to the King eternal, immortal, invisible, the only wise God. |
| Romans 11:33 | Marvels at the unsearchable riches, wisdom, and judgments of God. |
| Romans 11:34 | Asks who has known the mind of the Lord or who has become His counsellor. |
| Job 37:23 | Affirms the Almighty is exalted in power and judgment, beyond human reach. |
| Psalms 62:11 | Declares that God has spoken once, and power belongs exclusively to Him. |
| Jeremiah 32:17 | Proclaims that the Lord made heaven and earth by His great power, and nothing is too hard for Him. |
| 1 Chronicles 29:11 | Attributes all greatness, power, glory, victory, and majesty to the Lord forever. |
Human Frailty
Created Might Inevitably Stumbles and Fails
Even youths grow tired and weary, and young men stumble and fall;
Isaiah 40:30 (NIV)
It contrasts God's eternal vigor with the stark reality that even the most vigorous human beings will collapse without Him.
Scripture steadily strips away every illusion of human self-sufficiency. In Isaiah 40:30, the prophet observes that "even youths shall faint and be weary, and young men shall fall exhausted." If those possessing the peak of natural vigour, physical resilience, and youthful stamina inevitably collapse, no human resolve can sustain itself indefinitely. The psalmist confesses in Psalms 73:26 that mortal flesh and heart inevitably waste away, leaving God alone as the eternal rock of the soul. No project of human ingenuity stands on its own; Psalms 127:1 warns that unless the Lord builds the house, those who build labour in vain, and unless the Lord guards the city, the watchman stays awake to no purpose.
To place confidence in creaturely strength is therefore both foolish and hazardous. Through the prophet in Jeremiah 9:23, the Lord commands the mighty man not to boast in his might or the wise man in his wisdom. Trusting in natural capacity invites disaster; Jeremiah 17:5 pronounces a solemn curse upon anyone who trusts in mortal man and makes frail human flesh his arm. Military hardware and organized armies offer no true security. Psalms 33:16 explains that no earthly king is saved by the sheer size of an army, and Psalms 33:17 adds that a war horse is a vain hope for deliverance, unable to rescue by its great speed or strength.
True victory in spiritual and historical conflict relies on an entirely different plane of power. When Zerubbabel faced an insurmountable mountain of opposition, the word of the Lord came in Zechariah 4:6: "Not by might, nor by power, but by my Spirit, says the Lord of hosts." While Proverbs 21:31 notes that horses are prepared for battle, victory belongs wholly to the Lord. God routinely overturns worldly estimation; as 1 Corinthians 1:25 affirms, the apparent weakness of God is vastly stronger than men.
| Passage | What it says |
|---|---|
| Isaiah 40:30 | Observes that even youths grow faint and weary, and young men fall utterly exhausted. |
| Psalms 73:26 | Acknowledges that flesh and heart fail, but God remains the rock and portion of the heart forever. |
| Psalms 127:1 | Declares that builders and watchmen labour in vain unless the Lord builds the house and guards the city. |
| Jeremiah 9:23 | Commands that the mighty man must not boast in his might, nor the wise in their wisdom. |
| Jeremiah 17:5 | Warns of judgment upon the one who trusts in man and makes mere human flesh his arm of strength. |
| Psalms 33:16 | Explains that no king is saved by army size and no warrior delivered by great strength. |
| Psalms 33:17 | Declares a horse a vain hope for deliverance, unable to rescue by its great might. |
| Zechariah 4:6 | Warns that victory comes not by human might or power, but by the Lord's Spirit. |
| Proverbs 21:31 | Acknowledges that the horse is prepared for battle, but victory belongs entirely to the Lord. |
| 1 Corinthians 1:25 | Contrasts the apparent weakness of God as stronger than human strength. |
Power Imparted
The Lord Imparts Strength to the Weak
He gives strength to the weary and increases the power of the weak.
Isaiah 40:29 (NIV)
It shows that God specifically targets the destitute and powerless to receive His abundant strength.
The untiring God does not hoard His supreme might; He freely dispenses it to those who are depleted. In Isaiah 40:29, the prophet reveals that "he gives power to the faint, and to him who has no might he increases strength." God does not merely help the self-sufficient who have managed to advance most of the way; He seeks out the utterly exhausted and injects His life into their weakness. David rejoices in Psalms 28:7, declaring the Lord to be his strength and shield, while the sons of Korah celebrate in Psalms 46:1 that God is a very present help in trouble. When fear threatens to overwhelm, God commands courage in Isaiah 41:10, promising to uphold His servant with His righteous right hand.
This pattern reaches its pinnacle in the gospel, where divine strength is perfected through human limitation. When Paul pleaded for the removal of his painful thorn, Christ answered in 2 Corinthians 12:9 that His grace was sufficient, for power is perfected in weakness. Paul responded in 2 Corinthians 12:10 by taking pleasure in insults, hardships, and persecutions, knowing that whenever he was conscious of his own weakness, he was infused with Christ's genuine strength.
Throughout redemption history, believers continually celebrate this divine equipping. Moses sang at the Red Sea that the Lord was his strength and song (Exodus 15:2). David confesses his deep love for the Lord as his personal fortress (Psalms 18:1), testifying that it is God who equips him with strength for the path (Psalms 18:32). The Lord gives strength to His people and crowns them with peace (Psalms 29:11), blessing those whose pilgrimage is fortified from within (Psalms 84:5). Even when fields yield no food, the prophet Habakkuk rejoices that the Sovereign Lord is his strength, making his feet like the deer's (Habakkuk 3:19). Paul consequently prays in Colossians 1:11 that believers would be strengthened with all power according to God's glorious might.
| Passage | What it says |
|---|---|
| Isaiah 40:29 | States that God gives power to the faint and increases the strength of those who have no might. |
| Psalms 28:7 | Identifies the Lord as the believer's strength and shield, in whom the heart trusts and receives help. |
| Psalms 46:1 | Names God as our refuge and strength, an ever-present help in trouble. |
| Isaiah 41:10 | Assures believers not to fear, for God will strengthen, help, and uphold them with His righteous right hand. |
| 2 Corinthians 12:9 | Records Christ's promise that His grace is sufficient, because His power is perfected in human weakness. |
| 2 Corinthians 12:10 | Expresses joy in weaknesses and hardships for Christ's sake, because being weak leads to true divine strength. |
| Exodus 15:2 | Celebrates the Lord as the song and strength of His redeemed people. |
| Psalms 18:1 | David expresses his love to the Lord, identifying Him directly as his strength. |
| Psalms 18:32 | Praises God who equips His servant with strength and makes his way blameless. |
| Psalms 29:11 | Assures believers that the Lord gives strength to His people and blesses them with peace. |
| Psalms 84:5 | Blesses those whose strength is found entirely in the Lord. |
| Habakkuk 3:19 | Testifies that the Sovereign Lord is strength, making feet sure like the deer's. |
| Colossians 1:11 | Prayers for believers to be strengthened with all power according to God's glorious might. |
Waiting and Renewing
Patient Trust Renews and Sustains the Soul
but those who hope in the LORD will renew their strength. They will soar on wings like eagles; they will run and not grow weary, they will walk and not be faint.
Isaiah 40:31 (NIV)
It provides the classic promise that expectant reliance on Yahweh completely exchanges exhaustion for indefatigable vigor.
The conduit through which divine power enters human weakness is patient, expectant faith. In Isaiah 40:31, Scripture delivers the monumental promise: "they who wait for the Lord shall renew their strength; they shall mount up with wings like eagles; they shall run and not be weary; they shall walk and not faint." The Hebrew concept of waiting conveys an eager, bound tethering to God. It involves a total exchange of human fatigue for divine vitality. The psalmist confirms this discipline in Psalms 27:14, urging the weary heart to wait on the Lord and take courage. The prophet explains the posture required in Isaiah 30:15, reminding God's people that in returning and rest they are saved, and in quietness and trust is their strength. Because God's ways and thoughts are higher than ours (Isaiah 55:8; Isaiah 55:9), His timing and methods surpass human wisdom.
This active reliance sustains the believer from the moment of redemption through every earthly trial. Paul rests in the assurance that God will bring His begun work to full completion (Philippians 1:6). This enables the bold declaration of Philippians 4:13, where Paul testifies that he can do all things through Christ who continuously pours strength into him. Believers are summoned in Ephesians 6:10 to be strong in the Lord and in the strength of His might, putting on His spiritual armor. David similarly calls all who hope in the Lord to be courageous (Psalms 31:24), recalling how the Lord answered his cry by emboldening his soul (Psalms 138:3).
This reliance produces abiding gladness and courage. Nehemiah exhorted the weeping exiles that the joy of the Lord is your strength (Nehemiah 8:10). Joshua stepped into the promised land under the command to be strong and courageous because God was present with him (Joshua 1:9). Paul reminds Timothy that God gave us a spirit of power, love, and self-control rather than fear (2 Timothy 1:7), testifying at the end of his life that when all deserted him, the Lord stood by him and gave him strength (2 Timothy 4:17).
| Passage | What it says |
|---|---|
| Isaiah 40:31 | Promises that those who wait on Yahweh will exchange their strength, soar on wings like eagles, run, and not grow weary. |
| Psalms 27:14 | Exhorts the believer to wait for the Lord, be of good courage, and let the heart be strengthened. |
| Isaiah 30:15 | Affirms that salvation lies in returning and rest, and true strength is found in quietness and confidence. |
| Isaiah 55:8 | Reminds believers that God's thoughts and ways are vastly different from human thoughts. |
| Isaiah 55:9 | Declares that the heavens are higher than the earth, just as God's ways and thoughts surpass human ways. |
| Philippians 1:6 | Affirms confidence that He who began a good work in you will faithfully bring it to completion until Christ's day. |
| Philippians 4:13 | Confesses that the believer can endure all circumstances through Christ who gives inner strength. |
| Ephesians 6:10 | Commands believers to be strong in the Lord and in the power of His vast might. |
| Psalms 31:24 | Urges all who hope in the Lord to be strong and take heart. |
| Psalms 138:3 | Recounts how the Lord answered prayer by making the soul bold with stout strength. |
| Nehemiah 8:10 | Instructs the assembly that the joy of the Lord is their strength. |
| Joshua 1:9 | Commands courage and strength, founded on the promise of God's presence everywhere. |
| 2 Timothy 1:7 | Affirms God gives a spirit of power, love, and self-discipline rather than fear. |
| 2 Timothy 4:17 | Testifies that the Lord stood by Paul and gave him strength to preach fully. |
Where in the Bible
| Book | Passages |
|---|---|
| Exodus | 1 · Exodus 15:2 |
| Joshua | 1 · Joshua 1:9 |
| 1 Samuel | 1 · 1 Samuel 15:29 |
| 1 Chronicles | 1 · 1 Chronicles 29:11 |
| Nehemiah | 1 · Nehemiah 8:10 |
| Job | 1 · Job 37:23 |
| Psalms | 15 · Psalms 147:5, Psalms 62:11, Psalms 73:26, Psalms 127:1, Psalms 33:16, Psalms 33:17, Psalms 28:7, Psalms 46:1, Psalms 18:1, Psalms 18:32, Psalms 29:11, Psalms 84:5, Psalms 27:14, Psalms 31:24, Psalms 138:3 |
| Proverbs | 1 · Proverbs 21:31 |
| Isaiah | 9 · Isaiah 40:21, Isaiah 40:28, Isaiah 40:30, Isaiah 40:29, Isaiah 41:10, Isaiah 40:31, Isaiah 30:15, Isaiah 55:8, Isaiah 55:9 |
| Jeremiah | 3 · Jeremiah 32:17, Jeremiah 9:23, Jeremiah 17:5 |
| Habakkuk | 1 · Habakkuk 3:19 |
| Zechariah | 1 · Zechariah 4:6 |
| Romans | 2 · Romans 11:33, Romans 11:34 |
| 1 Corinthians | 1 · 1 Corinthians 1:25 |
| 2 Corinthians | 2 · 2 Corinthians 12:9, 2 Corinthians 12:10 |
| Ephesians | 1 · Ephesians 6:10 |
| Philippians | 2 · Philippians 1:6, Philippians 4:13 |
| Colossians | 1 · Colossians 1:11 |
| 1 Timothy | 1 · 1 Timothy 1:17 |
| 2 Timothy | 2 · 2 Timothy 1:7, 2 Timothy 4:17 |
The story in order
- Creation of the heavens and earth (c. 4000 BC) · Jeremiah 32:17 · God's great power made all things; nothing is too hard for Him.
- God's covenant with Israel (c. 1050 BC) · 1 Samuel 15:29 · God is the Strength of Israel, unchanging and true.
- David's praise for God's strength (c. 1000 BC) · Psalms 18:1 · David identifies the Lord as his personal strength and deliverer.
- Wisdom and power of God (c. 700 BC) · Isaiah 40:28 · God's power is infinite; He neither faints nor tires.
- Warning against human might (c. 600 BC) · Jeremiah 9:23 · Boasting in human strength, wisdom, or might is futile.
- God gives strength to the faint (c. 700 BC) · Isaiah 40:29 · God empowers those who lack might and increases strength.
- Victory by the Spirit, not might (c. 500 BC) · Zechariah 4:6 · Success comes through God's Spirit, not human power.
- Joy of the Lord is strength (c. 445 BC) · Nehemiah 8:10 · The joy found in the Lord provides essential strength.
- Jesus' ministry and teaching (AD 60-62) · Philippians 4:13 · Believers can do all things through Christ's empowering strength.
- Christ's power perfected in weakness (AD 55-57) · 2 Corinthians 12:9 · God's power is most evident and effective in human frailty.
- Paul's final testimony (c. AD 67) · 2 Timothy 4:17 · The Lord stood by Paul, giving him strength to complete his mission.
- Completion of the work of faith (AD 60-62) · Philippians 1:6 · God faithfully completes the work He starts in believers.
Human Might vs. Divine Strength
| Human Boasting | Divine Reality | Passage |
|---|---|---|
| Youths grow faint and weary. | God neither faints nor tires. | |
| Builders labour in vain without the Lord. | The Lord builds the house. | Psalms 127:1 |
| No king is saved by army size. | Power belongs exclusively to God. | |
| Man's arm of strength leads to judgment. | God gives power to the faint. | |
| Victory is not by human might or power. | Victory comes by the Lord's Spirit. | Zechariah 4:6 |
The Promise of Renewed Strength
| Condition | Promise | Passage |
|---|---|---|
| Those who wait on Yahweh | Will exchange their strength, soar like eagles. | Isaiah 40:31 |
| Those who trust in the Lord | Will be strengthened and have good courage. | Psalms 27:14 |
| Those who are weary and faint | God gives power and increases strength. | Isaiah 40:29 |
| Believers in Christ | Can endure all things. | Philippians 4:13 |
| Those who are strong in the Lord | Are clothed with His power. | Ephesians 6:10 |
God's Power Perfected in Weakness
| Human Weakness | Divine Strength | Passage |
|---|---|---|
| Flesh and heart may fail. | God remains the rock and portion of the heart. | Psalms 73:26 |
| Youths grow faint and weary. | God gives power to the faint. | |
| Human strength is limited. | God's power is perfected in weakness. | 2 Corinthians 12:9 |
| Believers may feel weak. | Christ gives inner strength to endure. | Philippians 4:13 |
| Paul faced hardships. | The Lord stood by him and gave him strength. | 2 Timothy 4:17 |
Key words
- Power (kōaḥ, כֹּחַ)
- The inherent ability or strength to do something; God's infinite, untiring might. · Psalms 62:11
- Strength (ʿōṣem, עֹצֶם)
- The quality or state of being physically strong; divine empowerment. · Psalms 28:7
- Faint (ʿāyēph, עָיֵף)
- To grow weak or lose strength; to become exhausted. · Isaiah 40:30
- Might (gĕbûrah, גְּבוּרָה)
- Great power or strength, often referring to human capability. · Zechariah 4:6
- Spirit (rûaḥ, רוּחַ)
- The divine power or influence of God. · Zechariah 4:6
- Wait (qāwâ, קָוָה)
- To remain in expectation; to trust and rely on God. · Isaiah 40:31
- Weakness (astheneia, ἀσθένεια)
- The state or condition of lacking physical strength or power. · 2 Corinthians 12:9
True power begins where self-sufficiency ends. When you are exhausted and spent, the Scriptures call you not to summon inner resolve, but to cast your entire weight upon the God who never grows weary. In Christ, your acknowledged weakness becomes the very dwelling place of His sustaining, unfailing strength.
48 passages, each cited once.
Scripture cited
- Isaiah 40:28-31
- 2 Corinthians 12:7-10
- Ephesians 6:10-13
- Philippians 4:11-13
- Psalms 73:25-26