But withal prepare me also a lodging: for I trust that through your prayers I shall be given unto you.
This prospect of Paul's visiting Colosse would secure a kindly reception for Onesimus, as Paul would know in person how he had been treated.
Your ... you - referring to Philemon, Apphia, Archippus, and the church in Philemon's house. The same expectation is expressed subsequently (Philippians 2:23-24).