2 Corinthians 3:1-6
3:1 Are we beginning to commend ourselves again? Or do we need, as some do, letters of recommendation to you, or from you? 2 You yourselves are our letter of recommendation, written on our hearts, to be known and read by all. 3 And you show that you are a letter from Christ delivered by us, written not with ink but with the Spirit of the living God, not on tablets of stone but on tablets of human hearts.
4 Such is the confidence that we have through Christ toward God. 5 Not that we are sufficient in ourselves to claim anything as coming from us, but our sufficiency is from God, 6 who has made us competent to be ministers of a new covenant, not of the letter but of the Spirit. For the letter kills, but the Spirit gives life.