When will the Church be raptured?
According to this teaching, the Church will not be raptured at Revelation chapter 4, as many suppose, but after the Great Tribulation, when the seventh (last) trumpet sounds and the mystery of God is finished, just before the wrath of God is poured out on the earth.
The rapture of the Church is not found in Revelation 4:1 when John hears a voice like a trumpet inviting him to "come up hither." That verse describes John being shown things to come; it never says John represents the Church, and it is unlawful to assign a symbolic meaning the Scripture itself does not give. If that verse meant the rapture of the whole Body of Christ, then no one on earth afterward would have the testimony of Jesus, yet Revelation goes on to speak of saints, martyrs, and believers who are very much still on the earth enduring the days of the Antichrist.
Instead, the rapture takes place at the sounding of the seventh trumpet, the true "last trump." First Corinthians 15:52 says, "In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed." Revelation 8:2 shows seven trumpets given to seven angels, and Revelation 10:7 says that in the days of the voice of the seventh angel, "the mystery of God should be finished." This mystery is Christ in us, the hope of glory (Colossians 1:26-28), the full revelation and glorification of the Body of Christ, which is not finished until that seventh trumpet sounds. This is the age of the Church on the earth being brought to a close.
Matthew 24 confirms the timing: "Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven... and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds." This gathering happens after the tribulation, not before it. Luke 21:23-28 gives the same order: the days of vengeance and distress upon Israel, then signs in the sun, moon, and stars, and only after that does the Son of man appear and our redemption draw nigh.
Revelation itself follows this same order. The sixth seal brings the earthquake, the sun turning black, the moon becoming as blood, and the stars falling, along with people crying out that the great day of the Lamb's wrath has come. Yet the wrath is not poured out yet, because two things must still happen: the 144,000 must be sealed (Revelation 7:2-4), and the Church must still be gathered, since believers are not appointed to wrath. It is only after this, in Revelation 7:9-14, that the great multitude which no man could number, clothed in white robes, stands before the throne and the Lamb. That multitude is the rapture of the Church, coming after the tribulation, after the sixth seal's cosmic signs, and just before the wrath of the seven last plagues is poured out on the earth.
The scriptures
After this I looked, and, behold, a door was opened in heaven: and the first voice which I heard was as it were of a trumpet talking with me; which said, Come up hither, and I will shew thee things which must be hereafter.
In a moment, in the twinkling of an eye, at the last trump: for the trumpet shall sound, and the dead shall be raised incorruptible, and we shall be changed.
And I saw the seven angels which stood before God; and to them were given seven trumpets.
But in the days of the voice of the seventh angel, when he shall begin to sound, the mystery of God should be finished, as he hath declared to his servants the prophets.
Even the mystery which hath been hid from ages and from generations, but now is made manifest to his saints: To whom God would make known what is the riches of the glory of this mystery among the Gentiles; which is Christ in you, the hope of glory: Whom we preach, warning every man, and teaching every man in all wisdom; that we may present every man perfect in Christ Jesus:
Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken: And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory. And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.
But woe unto them that are with child, and to them that give suck, in those days! for there shall be great distress in the land, and wrath upon this people. And they shall fall by the edge of the sword, and shall be led away captive into all nations: and Jerusalem shall be trodden down of the Gentiles, until the times of the Gentiles be fulfilled. And there shall be signs in the sun, and in the moon, and in the stars; and upon the earth distress of nations, with perplexity; the sea and the waves roaring; Men’s hearts failing them for fear, and for looking after those things which are coming on the earth: for the powers of heaven shall be shaken. And then shall they see the Son of man coming in a cloud with power and great glory. And when these things begin to come to pass, then look up, and lift up your heads; for your redemption draweth nigh.
And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood; And the stars of heaven fell unto the earth, even as a fig tree casteth her untimely figs, when she is shaken of a mighty wind. And the heaven departed as a scroll when it is rolled together; and every mountain and island were moved out of their places. And the kings of the earth, and the great men, and the rich men, and the chief captains, and the mighty men, and every bondman, and every free man, hid themselves in the dens and in the rocks of the mountains; And said to the mountains and rocks, Fall on us, and hide us from the face of him that sitteth on the throne, and from the wrath of the Lamb: For the great day of his wrath is come; and who shall be able to stand?
From the books
This answer is drawn from these passages in the Mary Banks Faith Library.