'Ink' in the Bible

Then Baruch said to them, “He dictated all these words to me, and I wrote them with ink on the book.”

being manifested that you are a letter of Christ, cared for 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.

Though I have many things to write to you, I do not want to do so with paper and ink; but I hope to come to you and speak face to face, so that your joy may be made full.

I had many things to write to you, but I am not willing to write them to you with pen and ink;