"He gives strength to the weary and increases the power of the weak. Even youths grow tired and weary, and young men stumble and fall; but those who hope in the Lord will renew their strength. They will soar on wings like eagles; they will run and not grow weary, they will walk and not be faint." Isaiah 40:29-31, NIV.
"The Lord is my light and my salvation; whom shall I fear? The Lord is the strength of my life; of whom shall I be afraid." Psalms 27:1, NKJV