Do you not know, have you not heard?
The LORD, the everlasting God, creator of the wide world,
grows neither weary nor faint;
no man can fathom his understanding.
He gives vigour to the weary,
new strength to the exhausted.
Young men may grow weary and faint,
even in their prime they may stumble and fall;
but those who look to the LORD will win new strength,
they will grow wings like eagles;
they will run and not be...
Isaiah 40:28–31