These verses are for the days when your own strength runs out: when you are tired, afraid, or facing something too big for you. Most of them were first spoken to people in exactly that place. Learn one, and it is there the next time you need it.
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.
We all feel tired and weak sometimes, but if you put your hope in the LORD, he will renew your strength.
Fear not, for I am with you; Be not dismayed, for I am your God. I will strengthen you. Yes, I will help you, I will uphold you with My righteous right hand.
You do not need to fear nor be dismayed because God will uphold you.
And He said to me, "My grace is sufficient for you, for My strength is made perfect in weakness." Therefore most gladly I will rather boast in my infirmities, that the power of Christ may rest upon me.
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