A.T. Robertson Commentary Acts 19:22

"And having sent into Macedonia two of them that ministered unto him, Timothy and Erastus, he himself stayed in Asia for a while." — Acts 19:22 (ASV)

Timothy and Erastus (Τιμοθεον κα Εραστον). Paul had sent Timothy to Corinth (1 Corinthians 4:17) and had requested kindly treatment of this young minister in his difficult task of placating the divided church (1 Corinthians 16:10–11) that he might return to Paul as he evidently had before Paul leaves Ephesus. He then despatched Titus to Corinth to finish what Timothy had not quite succeeded in doing with instructions to meet him in Troas. Now Timothy and Erastus (cf. Romans 16:23; 2 Timothy 4:20) go on to Macedonia to prepare the way for Paul who will come on later.

He himself stayed in Asia for a while (αυτος επεσχεν χρονον εις την Ασιαν). Literally, He himself had additional time in Asia. Second aorist active indicative of επεχω, old and common idiom, only here in the N.T. in this sense and the verb only in Luke and Paul. The reason for Paul's delay is given by him in 1 Corinthians 16:8f. , the great door wide open in Ephesus. Here again Luke and Paul supplement each other. Pentecost came towards the end of May and May was the month of the festival of Artemis (Diana) when great multitudes would come to Ephesus. But he did not remain till Pentecost as both Luke and Paul make plain.