Paul was ever reluctant to speak commendably of himself. It was too like boasting for him to be happy when engaged in it. Nevertheless, in order to refute those who denigrated his ministry, he had to indicate the marks of God’s blessing on his labours.

He had vindicated himself in his first epistle, 1 Cor 9:1-2, and doubtless he was charged by his opponents with going around commending himself. It was most likely their criticisms that drew his defensive answer in verse 2-3. He did not need to commend himself since the Corinthians were his commendation. They were indeed the seal of his apostleship. 

I. THE CHARACTER OF THE WITNESS OF THE TRUE CONVERTS TO CHRIST

Verse 1.

1. They are epistles of Christ. They have the etchings of the Holy Ghost upon their lives.

2. They were widely read. Known and read of all men. How widely circulated is the message of Christ written in the lives of true believers. 

3. They were easily understood. The world can tell the true from the fake believer. 

4. They proclaim the basic gospel truth. 

The change the sinner must undergo. 1 Thess 1:9. There has been a turning of the tide of their life.

How the change takes place. Surely, shall one say, in the LORD have I righteousness and strength, Isaiah 45:24.

5. They declare the power of the gospel. What sin had been in the lives of the Corinthians before the gospel came! 1 Cor 6:9-11.

6. They vindicate the claims of the gospel. There is mercy for the worst, victory for the lowest, lifting up for the downcast.