Isaiah 40:28-31

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. 

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; 31 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.

2 Corinthians 12:9,10

9But he said to me, "My grace is sufficient for you, for my power is made perfect in weakness." Therefore I will boast all the more gladly about my weaknesses, so that Christ's power may rest on me. 10That is why, for Christ's sake, I delight in weaknesses, in insults, in hardships, in persecutions, in difficulties. For when I am weak, then I am strong.

Philippians 4:12,13

12I know what it is to be in need, and I know what it is to have plenty. I have learned the secret of being content in any and every situation, whether well fed or hungry, whether living in plenty or in want. 13I can do everything through him who gives me strength.

1 Corinthians 1:20-31

20Where is the wise man? Where is the scholar? Where is the philosopher of this age? Has not God made foolish the wisdom of the world? 21For since in the wisdom of God the world through its wisdom did not know him, God was pleased through the foolishness of what was preached to save those who believe. 22Jews demand miraculous signs and Greeks look for wisdom, 23but we preach Christ crucified: a stumbling block to Jews and foolishness to Gentiles, 24but to those whom God has called, both Jews and Greeks, Christ the power of God and the wisdom of God. 25For the foolishness of God is wiser than man's wisdom, and the weakness of God is stronger than man's strength. 

26Brothers, think of what you were when you were called. Not many of you were wise by human standards; not many were influential; not many were of noble birth. 27But God chose the foolish things of the world to shame the wise; God chose the weak things of the world to shame the strong. 28He chose the lowly things of this world and the despised things-and the things that are not-to nullify the things that are, 29so that no one may boast before him. 30It is because of him that you are in Christ Jesus, who has become for us wisdom from God-that is, our righteousness, holiness and redemption. 31Therefore, as it is written: "Let him who boasts boast in the Lord."