28 Do you not know? Have you not heard? The LORD is the everlasting God, the Creator of the ends of the earth. He will not grow tired or weary, and his understanding no one can fathom.
References for Isaiah 40:28
29 He gives strength to the weary and increases the power of the weak.
30 Even youths grow tired and weary, and young men stumble and fall;
References for Isaiah 40:30