Insomuch - So that. This should be connected with Acts 5:12. Many miracles were performed by the apostles, “insomuch, etc.”
They brought forth - The people, or the friends of the sick, brought them forth.
Beds - κλινῶν klinōn. This word denotes usually the “soft” and “valuable” beds on which the rich commonly lay. And it means that the rich, as well as the poor, were laid in the path of Peter and the other apostles.
Couches - κραββάτων krabatōn. The coarse and hard couches on which the poor used to lie, Mark 2:4, Mark 2:9,Mark 2:11-12; Mark 6:55; John 5:8-12; Acts 9:33.
The shadow of Peter - That is, they were laid in the path so that the shadow of Peter, as he walked, might pass over them. Perhaps the sun was near setting, and the lengthened shadow of Peter might be thrown afar across the way. They were not able to approach him on account of the crowd, and they “imagined” that if they could “anyhow” come under his influence they might be healed. The sacred writer does not say, however, that any “were” healed in this way, nor that they were commanded to do this. He simply states the “impression” which was on the minds of the people that it “might be.” Whether they were healed by this, it is left for us merely to conjecture. An instance somewhat similar is recorded in Acts 19:12, where it is expressly said, however, that the sick were healed by contact with “handkerchiefs” and “aprons” that were brought from the body of Paul. Compare also Matthew 9:21-22, where the woman said respecting Jesus “If I may but touch his garment I shall be whole.”
Might overshadow - That his shadow might pass over them. Though there is no certain evidence that any were healed in this way, yet it shows the full belief of the people that Peter had the power of working miracles. “Peter” was supposed by them to be eminently endowed with this power, because it was by him that the lame man in the temple had been healed Acts 3:4-6, and because he had been most prominent in his addresses to the people. The persons who are specified in this verse were those who dwelt at Jerusalem.