12 So, when he had considered this, he came to the house of Mary, the mother of John whose surname was Mark, where many were gathered together praying.
13 And as Peter knocked at the door of the gate, a girl named Rhoda came to answer.
14 When she recognized Peter’s voice, because of her gladness she did not open the gate, but ran in and announced that Peter stood before the gate.
15 But they said to her, “You are beside yourself!” Yet she kept insisting that it was so. So they said, “It is his angel.”
16 Now Peter continued knocking; and when they opened the door and saw him, they were astonished.
17 But motioning to them with his hand to keep silent, he declared to them how the Lord had brought him out of the prison. And he said, “Go, tell these things to James and to the brethren.” And he departed and went to another place.
18 Then, as soon as it was day, there was no small stir among the soldiers about what had become of Peter.
19 But when Herod had searched for him and not found him, he examined the guards and commanded that they should be put to death. And he went down from Judea to Caesarea, and stayed there.
considered (v.12) = comprehended — understood what had happened
Mary (v.12) — her only mention in Scripture. She may have been a widow. She was rich enough to own a house in which “many” (v.12) could gather.
John whose surname was Mark (v.12) — “John” was his Hebrew name; “Mark” his Gentile one. From the various notices of him which occur in the New Testament, we may form an epitome of his history.
1) … He was cousin of Barnabas (Colossians 4:10); i.e. they were children of [siblings].
2) He was connected with Peter in his youth, and received spiritual help from him (1 Peter 5:13).
3) He accompanied Barnabas and Paul to Antioch, and, later, to Cyprus (13:4-5). He deserted them, however, at Perga (13:13), and for this reason Paul refused to take him as a fellow-worker during his second missionary journey, with the result that Mark accompanied Barnabas to Cyprus (15:36-39).
4) We then lose sight of him till he reappears with Paul at Rome, evidently a more consecrated man than formerly and the apostle’s accepted companion and co-worker (Colossians 4:10; Philemon 24). During Paul’s second imprisonment at Rome, we find the apostle bidding Timothy to come speedily and bring Mark with him (2 Timothy 4:11), as being “useful for ministering.”
5) 1 Peter 5:13 shows him again associated with Peter and suggests that he had visited some of those churches of Asia Minor to which that apostle is writing. His co-partnership with Peter may have been during the period which elapsed between his departure with Barnabas to Cyprus and his reappearance at Rome with Paul.
6) All that we know certainly, in addition, is that he was the writer of the second Gospel, in the composition of which he had, most probably, Peter’s help and advice. — Walker, pages 268-269
gate (v.13) — as in Acts 10:17 — vestibule — the passageway from the street to the inner courtyard of the house
girl (v.13) = maid — a servant — another hint of Mary’s wealth
Rhoda (v.13) = rose
angel (v.13) — Jews of that time thought each person had a guardian angel to protect him and which could assume the appearance of the one he protected. Those in Mary’s house may have meant this, or they might have thought Peter’s spirit or ghost was at the door.
James (v.17) — Our Lord’s brother. He stands forth to prominence here for the first time as a leader of the church in Jerusalem. In 15:13-21, we see him as president of the Council held in that city to consider the position of the Gentile churches; and other notices of him in the New Testament confirm the fact that he held a position in some respects analogous to that of the later episcopate (Galatians 1:19; 2:9, 12; Acts 21:18). He was, so to speak, head of the college of presbyters in Jerusalem. To him is to be ascribed the Epistle of James. He is known as “James the Just,” and was [supposedly] martyred in Jerusalem in A.D. 62, being thrown down from a pinnacle of the temple and then beaten to death with a fuller’s club. — Walker, page 271
another place (v.17) — we aren’t told where. He was back in Jerusalem in Acts 15:7-11.
examined (v.19) — probably with scourgings
put to death (v.19) — the penalty, under Roman law, for allowing a prisoner to escape
Rhoda, alone, demonstrated faith in this instance. Many commentaries make a point of showing how this incident demonstrates the effectiveness of prayer, but I think it points to something different. Those in Mary’s house were praying, but when they saw evidence that their prayer had been answered, they were “astonished” (v.16). The word means “distraught, bewitched, insane.” I think it’s obvious that, even at this early date, when God was still occasionally intervening physically, a supernatural answer to prayer was NOT the normal course of events.