To send Timothy. It appears that St. Paul could not send Timothy to Philippi till some time after his deliverance from prison, about the year 63 of Jesus Christ. (Tillemont)
In the succeeding verse, we see the high esteem in which Timothy was held by this apostle.
He had said, have fallen out unto the progress of the Gospel; so that my bonds became manifest in Christ throughout the whole prætorian guard. Philippians 1:12-13 Again, Yea, and if I am offered upon the sacrifice and service of your faith. Philippians 2:17 By these words he strengthened them. Perchance they might suspect that his former words were spoken just to comfort them. What then? I send Timothy unto you, says he; for they desired to hear all things that concerned him. And wherefore said he not, that you may know my state, but, that I may know yours? Because Epaphroditus would have reported his state before the arrival of Timothy. Wherefore further on he says, But I counted it necessary to send to you Epaphroditus, my brother Philippians 2:25; but I wish to learn of your affairs. For it is likely that he had remained long time with Paul through his bodily weakness. So that he says, I wish to know your state. See then how he refers everything to Christ, even the mission of Timoth...
He shows his love not only by telling them his news but also by asking for theirs. This is the mark of a soul that is constantly permeated with solicitude and consideration…. Why did he say not “so that you may know my affairs” but “so that I may know yours”? The reason is that Epaphroditus was going to bring news of him before Timothy. .