Paul can say he saw a light flash from “heaven” in Acts 9:3, and probably just mean “up” or “in the skies.” But, Peter’s observations about his vision open up the heavens for us:
Acts 10:9 About noon the next day, as they were on their journey and approaching the city, Peter went up on the roof to pray. 10 He became hungry and wanted something to eat; and while it was being prepared, he fell into a trance. 11 He saw the heaven opened and something like a large sheet coming down, being lowered to the ground by its four corners. 12 In it were all kinds of four-footed creatures and reptiles and birds of the air. 13 Then he heard a voice saying, ?Get up, Peter; kill and eat.?
Acts 11:9 But a second time the voice answered from heaven, ?What God has made clean, you must not call profane.? 10 This happened three times; then everything was pulled up again to heaven.
First, heaven is surely “up” here and surely the dwelling place of God, but it is the place out of which revelations are made or from which revelations drop into this world.
Second, hence we are led to think of heaven as, in part, the place of mysteries — where they are stored and from which place they are released for human gaze and back into which they are sent.
Third, the expansion of Israel to the Gentiles in mission seems to need special divine authorization to propel folks like Peter and others out.
Fourth, the expansion of Peter’s diet — kosher food laws — also needed a revelation from on high.