What did God say to Paul about his weakness?

Answer: My grace is sufficient

My grace is sufficient for you, for my power is made perfect in weakness.

“But He said to me, “My grace is sufficient for you, for My power is perfected in weakness.” Therefore I will boast all the more gladly in my weaknesses, so that the power of Christ may rest on me.”— 2 Corinthians 12:9 (BSB)