You people show [i.e., by your conversions] that you are a letter from Christ, delivered by us [i.e., the result of our ministry], not written with ink but with the Holy Spirit of the living God; not on stone tablets [i.e., as in the case with Moses' ministry], but on tablets of the human heart. [See Jer. 31:33; Heb. 8:10].

But I have this treasure in a mere ear then jar, to show that its amazing power belongs to God and not to me.

[Jer. 9:24 says], "But the person who boasts should boast about the Lord."