These going before - Going before Paul and Luke. Dr. Doddridge supposes that only Tychicus and Trophimus went before the others. Perhaps the Greek most naturally demands this interpretation.
Tarried for us - The word "us," here, shows that Luke had again joined Paul as his companion. In Acts 16:12 it appears that Luke was in Philippi, in the house of Lydia. Why he remained there, or why he did not attend Paul in his journey to Athens, Corinth, Ephesus, etc., is not known. It is evident, however, that he here joined him again.
At Troas - See the notes on Acts 16:8.

Tarried for us at Troas - See the preceding verse. Troas was a small town in Phrygia Minor, in the province called the Troad: see Acts 16:8.

These going before,.... The apostle into Asia, all but Sopater, who accompanied him:
tarried for us at Troas; a city in Asia Minor; see Acts 16:8 whither they went before hand a nearer way, to provide for the apostle, and where they waited for him, and for Sopater, and for Luke, the writer of this history, who appears from hence to be in company with the apostle, and for as many others as were along with him.

These going before--perhaps to announce and prepare for the apostle's coming.
tarried for us at Troas.