Isaiah 40:31 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.
Generations of believers have clung to this promise and found it true. I can’t tell you how many times people walking through crisis and difficult have told me that they have been sustained by God and never would have made it through without him.
The promise comes at the end of a long chapter in which God encourages his people to trust in him because he is the incomparable God. J. I. Packer, in chapter 8 of the classic Knowing God meditates on this passage in what (for me) has been a life-changing manner. Here’s a PDF of that passage:
Evidence of the importance of this promise for God’s people is the number of songs that have been written on this theme. Here are just a few:
Eagles Wings Hillsong
Never heard this one, but I kinda like it:
Run (Isaiah 40:31) by After the Chase
And, if taken as commentary on this verse:
You Raise Me Up