After greeting them he described, one thing at a time, what God had done among the Gentiles through his ministry.
In context
17When we reached Jerusalem the brothers and sisters welcomed us gladly. 18The next day Paul went with us to see James, and all the elders were present. 19After greeting them he described, one thing at a time, what God had done among the Gentiles through his ministry. 20When they heard it they praised God. Then they said to him: “You see, brother, how many thousands of believers there are among the Jews, and every one of them zealous for the law. 21They have been told about you that you teach all the Jews who live among the Gentiles to abandon Moses, telling them not to circumcise their children or follow our customs.