Albert Barnes Commentary Philemon 1:21

"Having confidence in thine obedience I write unto thee, knowing that thou wilt do even beyond what I say." — Philemon 1:21 (ASV)

Having confidence in thy obedience. That you would comply with all my expressed desires.

I wrote unto thee. "I have written to you;" that is, in this epistle.

Knowing that thou wilt also do more than I say. In all the respects which he had mentioned—in receiving Onesimus, and in his kind treatment of him. He had asked a great favour of him, but he knew that he would go even beyond what he had asked.