en_tn/2co/11/10.md

As the truth of Christ is in me, this

Paul is emphasizing that because his readers know that he tells the truth about Christ, they can know that he is telling the truth here. "As surely as you know that I truly know and proclaim the truth about Christ, you can know that what I am about to say is true. This"

this boasting of mine will not be silenced

This can be stated in active form. Alternate translation: "no one will be able to make me stop boasting and stay silent" (See: rc://en/ta/man/translate/figs-activepassive)

this boasting of mine

This refers to what Paul spoke about in (2 Corinthians 11:7-9).

parts of Achaia

"regions of Achaia." The word "parts" speaks of areas of land, not political divisions.