This seems appropriate for Christmas:
Do you not know
or have you not heard?
The Lord is the eternal God,
creator of the ends of the earth.
He does not faint nor grow weary,
and his knowledge is beyond scrutiny.
He gives strength to the fainting;
for the weak he makes vigor abound.
Though young men faint and grow weary,
and youths stagger and fall,
They that hope in the Lord will renew their strength,
they will soar as with eagles’ wings;
They will run and not grow weary,
walk and not grow faint.
— Isaiah 40:28-31