II Corinthians 3:2

our epistle--of recommendation. in our hearts--not letters borne merely in the hands. Your conversion through my instrumentality, and your faith which is "known of all men" by widespread report (Co1 1:4-7), and which is written by memory and affection on my inmost heart and is borne about wherever I go, is my letter of recommendation (Co1 9:2). known and read--words akin in root, sound, and sense (so Co2 1:13). "Ye are known to be my converts by general knowledge: then ye are known more particularly by your reflecting my doctrine in your Christian life." The handwriting is first "known," then the Epistle is "read" [GROTIUS] (Co2 4:2; Co1 14:25). There is not so powerful a sermon in the world, as a consistent Christian life. The eye of the world takes in more than the ear. Christians' lives are the only religious books the world reads. IGNATIUS [Epistle to the Ephesians, 10] writes, "Give unbelievers the chance of believing through you. Consider yourselves employed by God; your lives the form of language in which He addresses them. Be mild when they are angry, humble when they are haughty; to their blasphemy oppose prayer without ceasing; to their inconsistency, a steadfast adherence to your faith."

The apostle makes an apology for his seeming to commend himself, and is careful not to assume too much to himself, but to ascribe all praise unto God (Co2 3:1-5). He then draws a comparison between the Old Testament and the New, and shows the excellency of the later above the former (Co2 3:6-11), whence he infers what is the duty of gospel ministers, and the advantage of those who live under the gospel above those who lived under the law (Co2 3:12 to the end).