but those who wait for the Lord 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.
qui autem sperant in Domino mutabunt fortitudinem, assument pennas sicut aquilæ: current et non laborabunt, ambulabunt et non deficient.Isaias 40:31 · Clementine Vulgate
Explanation — not a translation
In brief
Isaiah 40:31 promises that “those who wait for the LORD will renew their strength.” It is the last line of a chapter written to comfort a discouraged people, and its strength is given, not generated: it comes from the God who “doesn’t faint” and “gives power to the weak.”
The setting
Isaiah 40 marks a turn in the book. The earlier chapters are dominated by warning and judgment. Chapter 40 opens with tenderness instead.
“Comfort, comfort My people,” says your God.
“Speak comfortably to Jerusalem, and call out to her that her warfare is accomplished, that her iniquity is pardoned, that she has received of the Lord’s hand double for all her sins.”
Consolamini, consolamini, popule meus, dicit Deus vester. Loquimini ad cor Jerusalem, et advocate eam, quoniam completa est malitia ejus, dimissa est iniquitas illius: suscepit de manu Domini duplicia pro omnibus peccatis suis.Isaias 40:1–2 · Clementine Vulgate
“Comfort, comfort My people”: Jerusalem’s hard service is over and her guilt is pardoned.
Chapters 40–55 speak to Jews living in exile in Babylon in the sixth century BC, promising that God will bring them home. Many scholars think these chapters come from a later prophet in the tradition of Isaiah of Jerusalem; others, following older Jewish and Christian tradition, hold that Isaiah himself foresaw the exile. Either way, the original hearers were people far from home who had waited a long time.
The chapter’s opening voice, “Prepare the way of the LORD in the wilderness,” is applied in all four Gospels to John the Baptist (Matthew 3:3), and Catholics hear Isaiah 40 read in Advent.
The complaint behind the promise
Verse 31 answers a complaint. The exiles were saying that God no longer saw them.
Why do you say, Jacob,
and speak, Israel,
“My way is hidden from the Lord,
and the justice due me is disregarded by my God”?
Haven’t you known?
Haven’t you heard?
The everlasting God, the Lord,
the Creator of the ends of the earth, doesn’t faint.
He isn’t weary.
His understanding is unsearchable.
He gives power to the weak.
He increases the strength of him who has no might.
Even the youths faint and get weary,
and the young men utterly fall;
but those who wait for the Lord 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.
Quare dicis, Jacob, et loqueris, Israël: Abscondita est via mea a Domino, et a Deo meo judicium meum transivit? Numquid nescis, aut non audisti? Deus sempiternus Dominus, qui creavit terminos terræ: non deficiet, neque laborabit, nec est investigatio sapientiæ ejus. Qui dat lasso virtutem, et his qui non sunt, fortitudinem et robur multiplicat. Deficient pueri, et laborabunt, et juvenes in infirmitate cadent; qui autem sperant in Domino mutabunt fortitudinem, assument pennas sicut aquilæ: current et non laborabunt, ambulabunt et non deficient.Isaias 40:27–31 · Clementine Vulgate
“My way is hidden from the LORD” — and the reply: the everlasting God does not grow weary.
The prophet does not argue that the exiles are strong. He admits that even the young “faint and get weary” (verse 30). The answer is to look at God instead: the Creator who calls the stars by name (verse 26) has strength to spare and gives it away.
Waiting, eagles, walking
- “wait for the LORD” — the Hebrew verb carries the sense of hopeful expectation, which is why some translations render it “hope in the LORD.” It is not idle passivity but leaning one’s weight on God while the answer has not yet come.
- “wings like eagles” — the eagle recalls the exodus, where God says He bore Israel “on eagles’ wings” (Exodus 19:4; compare Deuteronomy 32:11). Psalm 103:5 uses the same bird for renewed youth.
- “walk, and not faint” — many readers notice the order: soaring, then running, then walking. The last and humblest gift may be the most needed. On some days the promise is simply strength to keep going.
What it promises — and what it doesn’t
The verse promises renewed strength to those who wait for God. It does not promise physical stamina on demand, success in a race or a career, or a quick end to the waiting. The first hearers still had a journey ahead of them. The verses for athletes collection uses the verse with that context in mind.
How Christians read it
Christians read Isaiah 40 as part of the good news that God comes to save His people, fulfilled in Jesus. Paul’s words in 2 Corinthians 4:16, “our inward person is renewed day by day,” and 2 Corinthians 12:9, strength made perfect in weakness, echo the same pattern: strength is given to those who know they lack it.
Read it with
Isaiah 40:9–11 pictures God gathering His flock like a shepherd. Lamentations 3:25–26 speaks of waiting quietly for the LORD. The Strength and Hope pages gather related passages.