John Calvin Commentary 1 Corinthians 4:17

"For this cause have I sent unto you Timothy, who is my beloved and faithful child in the Lord, who shall put you in remembrance of my ways which are in Christ, even as I teach everywhere in every church." — 1 Corinthians 4:17 (ASV)

For this cause. The meaning is: “That you may know what my way of life is, and whether I am worthy to be imitated, listen to what Timothy has to say, who will be prepared to be a faithful witness of these things.” As there are two things that give credibility to a person’s testimony—a knowledge of the things he recounts, and fidelity—he lets them know that Timothy possesses both of these.

For in calling him his dearly beloved son, he implies that he knew him intimately and was acquainted with all his affairs; furthermore, he speaks of him as faithful in the Lord. He also charges Timothy with two things:

1. To remind the Corinthians of those things which they should have remembered themselves (and in this he tacitly rebukes them).
2. To testify to them how consistent and steadfast his way of teaching was in every place.

Now, it is probable that he had been assailed by the slanders of the false apostles, as if he assumed more authority over the Corinthians than he did over others, or as if he conducted himself very differently in other places; for it is not without good reason that he wishes this to be testified to them. It is, therefore, the role of a prudent minister to regulate his procedure and observe such a method of instruction that no such objection may be brought against him, and that he will be prepared to answer on the same ground as Paul does.