'Weakness' in the Bible

Who is weak, and I do not feel [his] weakness? Who is made to sin, and I am not on fire [with sorrow and concern]?

If I have to boast, I will boast of what pertains to my weakness.

And he said unto me, My grace is sufficient for thee: for my strength is made perfect in weakness. Most gladly therefore will I rather glory in my infirmities, that the power of Christ may rest upon me.

For though he was crucified through weakness, yet he liveth by the power of God. For we also are weak in him, but we shall live with him by the power of God toward you.