Isaiah 40:29-31

29 He gives power to the faint,
and to him who has no might he increases strength.
30 Even youths shall faint and be weary,
and young men shall fall exhausted;
31 but a they who wait for the  Lord shall renew their strength;
they shall mount up with wings b like eagles;
they shall run and not be weary;
they shall walk and not faint.
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