Greetings:
The Society's explanation is not out of harmony with what other commentators have said about this passage.
Coffman's NT:
It is his angel ...
This verse proves that in the apostolic church the Christians believed that every person has a guardian angel; but it is uncertain what deductions should be made from this fact. Jesus apparently justified such a view by his reference to the angels of little children in Matthew 18:10, as being angels of the highest rank. See in my Commentary on Matthew, under Matt. 18:10 , and in my Commentary on Hebrews, Heb. 1:14. The thinking of those who said this seems to be that "Since Herod has already killed Peter, it must be his personal angel who is knocking at the gate."
Peter kept on knocking, however; and the stunned hearers finally let him in.
Excerpt from Henry Complete:
She ran in, and probably went up to an upper room where they were together, and told them that Peter was certainly at the gate, though she had not courage enough to open the gate, for fear she should be deceived, and it should be the enemy. But, when she spoke of Peter?s being there, they said, "Thou art mad; it is impossible it should be he, for he is in prison.?? Sometimes that which we most earnestly wish for we are most backward to believe, because we are afraid of imposing upon ourselves, as the disciples, who, when Christ had risen, believed not for joy. However, she stood to it that it was he. Then said they, It is his angel, v. 15. First, "It is a messenger from him, that makes use of his name;?? so some take it; angelos often signifies no more than a messenger. It is used of John?s messengers (Lu. 7:24, 27), of Christ?s, Lu. 9:52. When the damsel was confident it was Peter, because she knew his voice, they thought it was because he that stood at the door had called himself Peter, and therefore offer this solution of the difficulty, "It is one that comes with an errand from him, and thou didst mistake as if it had been he himself.?? Dr. Hammond thinks this the easiest way of understanding it. Secondly, "It is his guardian angel, or some other angel that has assumed his shape and voice, and stands at the gate in his resemblance.?? Some think that they supposed his angel to appear as a presage of his death approaching; and this agrees with a notion which the vulgar have, that sometimes before persons have died their ward has been seen, that is, some spirit exactly in their likeness for countenance and dress, when they themselves have been at the same time in some other place; they call it their ward, that is, their angel, who is their guard. If so, they concluded this an ill omen, that their prayers were denied, and that the language of the apparition was, "Let it suffice you, Peter must die, say no more of that matter.?? And, if we understand it so, it only proves that they had then such an opinion of a man?s ward being seen a little before his death, but does not prove that there is such a thing. Others think they took this to be an angel from heaven, sent to bring them a grant to their prayers. But why should they imagine that angel to assume the voice and shape of Peter, when we find not any thing like it in the appearance of angels? Perhaps they herein spoke the language of the Jews, who had a fond conceit that every good man has a particular tutelar angel, that has the charge of him, and sometimes personates him. the heathen called it a good genius, that attended a man; but, since no other scripture speaks of such a thing, this alone is too weak to bear the weight of such a doctrine. We are sure that the angels are ministering spirits for the good of the heirs of salvation, that they have a charge concerning them, and pitch their tents round about them; and we need not be solicitous that every particular saint should have his guardian angel, when we are assured he has a guard of angels. (5.) At length they let him in (v. 16): He continued knocking though they delayed to open to him, and at last they admitted him. The iron gate which opposed his enlargement opened of itself, without so much as once knocking at it; but the door of his friend?s house that was to welcome him does not open of its own accord, but must be knocked at, long knocked at; lest Peter should be puffed up by the honours which the angel did him, he meets with this mortification, by a seeming slight which his friends put upon him. But, when they saw him, they were astonished, were filled with wonder and joy in him, as much as they were but just now with sorrow and fear concerning him. It was both surprising and pleasing to them in the highest degree. (6.) Peter gave them an account of his deliverance. When he came to the company that were gathered together with so much zeal to pray for him, they gathered about him with no less zeal to congratulate him on his deliverance; and herein they were so noisy that when Peter himself begged them to consider what peril he was yet in, if they should be overheard, he could not make them hear him, but was forced to beckon to them with the hand to hold their peace, and had much ado thereby to command silence, while he declared unto them how the Lord Jesus had by an angel brought him out of prison; and it is very likely, having found them praying for his deliverance, he did not part with them till he and they had together solemnly given thanks to God for his enlargement; or, if he could not stay to do it, it is probable they staid together to do it; for what is won by prayer must be worn with praise; and God must always have the glory of that which we have the comfort of. When David declares what God had done for his soul, he blesses God who had not turned away his prayer, Ps. 66:16, 20.
Wesley:
AC 12:15 They said, Thou art mad - As we say, Sure you are not in your senses to talk so. It is his angel - It was a common opinion among the Jews, that every man had his particular guardian angel, who frequently assumed both his shape and voice. But this is a point on which the Scriptures are silent.
People?s NT:
AC 12:13 13-17. A damsel came to hearken. It was in the night, and they were Christians. The knocker might be an enemy or a friend. The damsel, a maid-servant, had charge of the door. When she knew Peter's voice. In answer to her question who might be at the door. Instead of opening, in her gladness, she flew to tell the good news, a touch of nature. It is his angel. The Jews held that every one had his guardian angel, and they thought his angel had assumed Peter's voice. A mistake, and Luke does not say whether the idea on which it was based is true or not. They were astonished. The
But Notice how Gill NT has a slightly different view:
it is his angel;
not his tutelar or guardian angel, everyone having, as some think, a particular angel to attend him; whereas sometimes one angel attends many persons, and sometimes many angels encamp about, and are a guard to a single saint; nor did they think it was an angel sent to give notice of his death, as some persons, by one means or another, have had previous notices of the death of their friends; but rather, that it was an angel in Peter's shape, who had something to communicate: and this agrees with the notions of the Jews, who think that angels do assume the shapes of men on certain occasions: so they say , when Moses was in danger in Pharaoh's court, God sent Michael, the prince of the host of heaven, "in the shape of an executioner"; who brought him at once out of Egypt, and set him at the border of it, the distance of three days journey: Bar Kaphra says , an angel descended (hvm twmdb) , "in the likeness of Moses", and caused him to flee, and they thought the angel had been Moses: and so it is elsewhere said , that an angel descended "in the likeness of Solomon", sitting upon his throne: there are some who think, that the sense of the brethren praying for Peter, was not that it was an angel, a celestial spirit, but a messenger sent by Peter from the prison on some errand: who represented him, or mentioning his name, the damsel took him for Peter himself. Beza's ancient copy reads, "then said they unto her, perhaps it is his angel", and so the Syriac version.
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I just want to add my comments. As you can see there are two views. The one most favoured being that they thought it to be Peter's guardian angels as some of the Jews may have believed. Luke is just recording (after the fact) what was reportedly said without commenting upon the superstition/belief itself. That seems to be the Society's view too.
The second minority view is what Gill is up to and I think he is on the right trail. We must remember that the aramaic word for Angel basically means "messenger" so it is very possible that the persons thought that the person knocking was a messenger from Peter from prison and it is only in the later translations into Latin and Greek that the terms for Angel were used as it is these terms that are present in the oldest manuscripts that are extant. But it may not have been so originally with Luke's autograph, the word may have been messenger. Only when it came very shortly to be translated into the word for Angel did then the need to find some particular explanation like that they might have believed in Guardian Angels, etc. arise out of what may have been just a very innocuous and rather pedestrian passage.
-Eduardo
PS: Oh and by the way in case it wasn't obvious from the above your assertion/theory that the disciples "OBVIOUSLY thought that persons went to heaven and became angels" is wrong.