In Revelation 7:14 the group of people are said to be those who came out of the “great tribulation” yet the 2nd half of the seven years hasn’t started. Great Tribulation is the same word Jesus used in Mt. 24:21 when referring to the 2nd half of that seven year period. What do you make of that?
The Greek word translated “out of” in Rev. 7:14 means to be out of both the place and time of the event being referenced, in this case the Great Tribulation.
What it means is that the large group dressed in white that John saw will arrive in Heaven after the church gets there, but before the Great Tribulation begins.
Some try to say this group is the Church, but they can’t be because they don’t arrive in Heaven til Rev. 7, and their destiny is to serve God day and night in His Temple (Rev. 7:15).
The Church is the Bride of Christ who is seen in heaven in Rev. 5 and whose destiny is to reign with Him. (Rev. 5:10)