Now if Timotheus come - Paul had sent Timothy to them (see the note at 1 Corinthians 4:17-18), but as he had many churches to visit, it was not absolutely certain that he would go to Corinth.
May be with you without fear - Let him be received kindly and affectionately. Timothy was then a young man; Acts 16:1-3; 1 Timothy 4:12. There might be some danger that he might feel himself embarrassed among the rich, the frivilous, and the great. Paul, therefore, asks them to encourage him, to receive him kindly, and not to embarrass him. Perhaps, also, there may be some reference to the false teachers whom Timothy might be called on to oppose. They were powerful, and they might endeavor to intimidate and alarm him. Paul, therefore, asks the church to sustain him in his efforts to defend the truth.
For he worketh the work of the Lord - He is engaged in the service of the Lord; and he is worthy of your confidence, and worthy to be sustained by you.