Hi CS,
My apologies to you if I didn't respond to something from you in another thread.
The Post Mill position views the "great tribulation" as something that was prophesied about Jerusalem's destruction in 70 AD. The Sermon on the Mount in Matt 24, Mark 13 and Luke 21 are past events about the generation He spoke to, as He said more than once in His denunciation of them, speaking directly to them, "THIS generation" (the ones he was speaking to). If you read those prophetic statements by Christ, it's clear He was speaking about what was going to come upon them, their judgement. The prophesies in the O.T. warned against their faithlessness and them becoming "dull of hearing", "shutting their eyes", etc., and even John the Baptist warned them of needing to flee from "the wrath to come" and that "the axe is laid to the root of the tree", etc.
It's a subject that should be looked into, but eschatology is not the all that ends all. I do think however, it is important but not to the point of dividing or breaking fellowship with folks over.
The resurrection at Christ's glorious coming for us is what we are to look for next regardless of how soon or how far away that is. Our obligation and privilege now, is to share, preach and proclaim salvation to all who will listen, "that Christ died for our sins according to the scriptures, and that He was buried and rose again the third day, according to the scriptures (1 Cor. 15:3, 4). And "For by grace are ye saved through faith, and that not of yourselves. It is the gift of God, not of works, lest any man should boast" (Eph. 2:8,9). We are saved by faith alone in Christ's finished work. I'm sure we can agree on that brother.
Blessings.