I am sending him back. You therefore receive him, that is, my own heart, whom I wished to keep with me, that on your behalf he might minister to me in my chains for the gospel. But without your consent I wanted to do nothing, that your good deed might not be by compulsion, as it were, but voluntary. Philemon 1:12-14

The Apostle Paul is now making the heartbreaking decision to send Onesimus back to Colossae, so why is he doing this? First reason is Onesimus is now a Born Again Christian, a brother in Christ, and he wants to make amends with Philemon, who was his master and whom he stole money from. Paul is pleading with Philemon and the Church of Colossae to forgive and accept Onesimus as their brother in Christ.

Secondly, Paul believes Onesimus will be very useful for the Church of Colossae. Onesimus has been a great help to Paul, however the Apostle knows his days are numbered, while in the Roman prison, Paul will eventually be beheaded and fulfill his race for Christ. 

Now during this exchange, we learn of another faith servant named Tychicus. This brother may not be a household name like Paul, but he is mentioned multiple times in the New Testament (Acts 20:4, Romans 15:25-26, Ephesians 6:21) In the epistle to the Colossians , its stated this about Tychicus

7Tychicus, a beloved brother, faithful minister, and fellow servant in the Lord, will tell you all the news about me. 8I am sending him to you for this very purpose, that [b]he may know your circumstances and comfort your hearts, 9with Onesimus, a faithful and beloved brother, who is one of you. They will make known to you all things which are happening here. (Colossians 4:7-9)

The Apostle Paul has sent Onesimus back with Tychicus to Colossae, its clear Paul has great trust in Tychicus, and respects him as a faithful minister in Christ. Paul is entrusting this Epistle to Philemon, will be delivered by Tychicus with Onesimus. I’m sure with Tychicus great reputation in the Church, it will be more appealing for the Church of Colossae to accept Onesimus back as a brother in Christ

Notice Paul states “But without your consent I wanted to do nothing” meaning Paul is not forcing Philemon to forgive and accept Onesimus, Paul is pleading as a brother and Apostle, to trust him , and the testimony of Tychicus, the Onesimus is redeemed and Born Again!