Timothy was one of the preachers who had been with Paul since the beginning of the work in Corinth (Acts 19:5; 2 Corinthians 1:19). Perhaps he and Paul had agreed that he would visit Corinth after travelling through Macedonia (see Acts 19:22).
Timothy’s close acquaintance with the Corinthians and his close association with Paul would give him the moral authority to restore unity in the Corinthian church. Clearly, Paul is concerned not only with the Corinthian church’s internal unity. He also wants to preserve unity between the Corinthian church and every church
in the rest of the empire.
17 That is why I sent you Timothy, my beloved and faithful child in the Lord, to remind you of my ways in Christ, as I teach them everywhere in every church.