In general, the “pre-trib” vs. “post-trib” terminology is most commonly used by Protestant groups in reference to false teachings concerning a bodily “rapture” of believers into the air where they will meet Christ prior to reigning with Him for 1,000 years on earth before the Great Judgment. Since the Orthodox and Apostolic faith never held to such a belief in a 1,000 year reign of the believers with Christ on earth following a period of Great Tribulation, nor separated the Great Judgment from the Second Coming, there was never a need to figure out whether believers would be “raptured” prior to or after this period of Great Tribulation preceding this 1,000 year earthly reign. So, the pre-trib/post-trib terminology should probably not be spoken of in the context of Orthodox teaching concerning the last days and the Second Coming since the terms themselves are bound up with heretical ideas that the Orthodox Church never held.
Now, concerning “tribulations”, in the Gospels and throughout the New Testament we are told that in this world we cannot escape tribulations, and the Lord also speaks of specific tribulations such as would occur with the fall of Jerusalem and prior to the Second Coming. Regarding the tribulations that all Christians must pass through, the Lord said to his disciples that “In the world you will have tribulation” (John 16:33), in the Book of Acts St. Paul says that “we must through much tribulation enter into the kingdom of God” (Acts 14:22), St. Paul tells the Romans that we must be “patient in tribulation” (Romans 12:12), etc.
In addition to the general tribulations and trials that all the faithful must experience and pass through in this life in order to enter the kingdom of God, the Lord also spoke of the tribulation that would occur with the destruction of Jerusalem, saying, “For then there will be great tribulation, such as has not been since the beginning of the world until this time, no, nor ever shall be.” (Matt 24:21).
Concerning this tribulation, St. John Chrisostom says:
Seest thou that His discourse is addressed to the Jews, and that He is speaking of the ills that should overtake them? For the apostles surely were not to keep the Sabbath day, neither to be there, when Vespasian did those things. For indeed the most part of them were already departed this life. And if any was left, he was dwelling then in other parts of the world.
But wherefore neither “in the winter, nor on the Sabbath day?” Not in the winter, because of the difficulty arising from the season; not on the Sabbath day, because of the absolute authority exercised by the law. For since they had need of flight, and of the swiftest flight, but neither would the Jews dare to flee on the Sabbath day, because of the law, neither in winter was such a thing easy; therefore, “Pray ye,” saith He; “for then shall be tribulation, such as never was, neither shall be.”
And let not any man suppose this to have been spoken hyperbolically; but let him study the writings of Josephus, and learn the truth of the sayings. For neither can any one say, that the man being a believer, in order to establish Christ’s words, hath exaggerated the tragical history. For indeed He was both a Jew, and a determined Jew, and very zealous, and among them that lived after Christ’s coming.
What then saith this man? That those terrors surpassed all tragedy, and that no such had ever overtaken the nation. For so great was the famine, that the very mothers fought about the devouring of their children, and that there were wars about this; and he saith that many when they were dead had their bellies ripped up….
So, according to St. John Chrysostom, the tribulations spoken of in Matthew 24:21 refer to the time of the destruction of Jerusalem. The Lord also speaks of the tribulation that will occur prior to the Second Coming, saying,
“Then if anyone says to you, 'Look, here is the Christ!' or 'There!' do not believe it. For false christs and false prophets will rise and show great signs and wonders to deceive, if possible, even the elect. See, I have told you beforehand. Therefore if they say to you, 'Look, He is in the desert!' do not go out; or 'Look, He is in the inner rooms!' do not believe it. For as the lightning comes from the east and flashes to the west, so also will the coming of the Son of Man be. For wherever the carcass is, there the eagles will be gathered together. "Immediately after the tribulation of those days the sun will be darkened, and the moon will not give its light; the stars will fall from heaven, and the powers of the heavens will be shaken. Then the sign of the Son of Man will appear in heaven, and then all the tribes of the earth will mourn, and they will see the Son of Man coming on the clouds of heaven with power and great glory. (Matt 24:23-30)
Concerning this tribulation, St. John Chrysostom says in the same homily:
Of the tribulation of what days doth He speak? Of those of Antichrist and of the false prophets? For there shall be great tribulation, there being so many deceivers. But it is not protracted to a length of time. For if the Jewish war was shortened for the elect’s sake, much more shall this temptation be limited for these same’s sake. Therefore, He said not, “after the tribulation,” but IMMEDIATELY “after the tribulation of those days shall the sun be darkened,” for almost at the same time all things come to pass. For the false prophets and false Christs shall come and cause confusion, and immediately He Himself will be here. Because no small turmoil is then to prevail over the world.
But how doth He come? The very creation being then transfigured, for “the sun shall be darkened,” not destroyed, but overcome by the light of His presence; and the stars shall fall, for what shall be the need of them thenceforth, there being no night? and “the powers of Heaven shall be shaken,” and in all likelihood, seeing so great a change come to pass. For if when the stars were made, they trembled and marvelled (“for when the stars were made, all angels,” it is said, “praised Me with a loud voice”); much more seeing all things in course of change, and their fellow servants giving account, and the whole world standing by that awful judgment-seat, and those who have lived from Adam unto His coming, having an account demanded of them of all that they did, how shall they but tremble, and be shaken?
As St. John Chrysostom points out, the tribulation spoken of here immediately precedes the Second Coming of Christ, and with the Second Coming occurs the Great Judgment. In Protestant “rapture” teaching, believers are “raptured” up into the air where the meet Christ prior to reigning with Christ on earth for 1,000 years. With this comes the question of whether believers will be “raptured” in this way prior to or after the Great Tribulation and the Second Coming. However, they then separate the Second Coming from the Great Judgment and introduce a great deal of falsehood and confusion into these events. So, again, since pre-trib/post-trib terminology is used in reference to teachings not held by the Orthodox Church (rapture and 1,000 year earthly reign), Orthodox teaching cannot be properly represented using the pre-trib/post-trib terminology.