A.T. Robertson Commentary Acts 10:3

"He saw in a vision openly, as it were about the ninth hour of the day, an angel of God coming in unto him, and saying to him, Cornelius." — Acts 10:3 (ASV)

Coming in (εισελθοντα). Ingressive second aorist active participle, not present. So punctiliar, "saw come," not "saw coming." So also "say" or "speak," not "saying." Luke repeats the account of this vision to Cornelius twice (10:30; 11:13) and also the story of the vision to Peter (10:1-16,28; 11:5).