Matthew Poole and continuators on Acts 21:19

19 And when he had saluted them, he declared particularly what things God had wrought among the Gentiles q by his ministry.

God had so done those marvellous works, that they ought to be had in remembrance; and this was said by the Apostle, that God might not lose the Glory, nor the Church the benefit of any of those great things which God had wrought: Otherwise, St. Paul acknowledges that he was the least of the Apostles, and not meet to be called an Apostle, 1 Cor. 15.9. and all his power was ministerial, he was only an Instrument in Gods hand, to be acted by him, as Chap. 20.24.