It is highly observable, that the apostle wraps up his praise of men in praise to God; giving him the glory. Your faith groweth — Probably he had heard from them since his sending the former letter. Aboundeth — Like water that overflows its banks, and yet increaseth still.
Related Commentaries of 2 Thessalonians 1:3
2 Thessalonians 1:3
3 We are bound to thank God always for you, brethren, as it is meet, because that your faith groweth exceedingly, and the charity of every one of you all toward each other aboundeth;