Isaiah 40:10-11 Behold, the Lord God shall come with a strong hand, and His arm shall rule for Him; Behold, His reward is with Him, and His work before Him. He will feed His flock like a shepherd; He will gather the lambs with His arm, and carry them in His bosom, and gently lead those who are with young. 

Isaiah 40:28-31 Have you not known? Have you not heard? The Everlasting God, the Lord, the Creator of the ends of the earth, neither faints nor is weary. His understanding is unsearchable. He gives power to the weak, and to those who have no might He increases strength. Even the youths shall faint and be weary, and the young men shall utterly fall, but those who wait on the Lord shall renew their strength; they shall mount up with wings like eagles, they shall run and not be weary, they shall walk and not faint.