Charles Ellicott Commentary Revelation 15:5

"And after these things I saw, and the temple of the tabernacle of the testimony in heaven was opened:" — Revelation 15:5 (ASV)

And after that . . .—Better, And after these things I saw, and there was opened the temple of the tabernacle of the testimony (or, witness) in the heaven. This temple is called the temple of the tabernacle of the testimony; the expression sounds cumbersome, but it is nevertheless suitable.

Saint Stephen spoke of the tabernacle of witness in the wilderness, which was made after the pattern shown on the mountain (Acts 7:44). The tabernacle was rightly called the tabernacle of witness, for it contained the ark of the testimony with the Law of God, and was a perpetual witness of God’s presence among His people. The temple of the tabernacle then is the shrine, or inner sanctuary, of the heavenly true tabernacle, after the pattern of which the tabernacle of Moses was fashioned, which is now opened.