Are we beginning to commend ourselves again? Or like some, do we need letters of recommendation to you or from you?
References for 2 Corinthians 3:1
You yourselves are our letter, written on our hearts, recognized and read by everyone,
since it is plain that you are Christ's letter, produced by us, not written with ink but with the Spirit of the living God; not on stone tablets but on tablets that are hearts of flesh.
References for 2 Corinthians 3:3