If you ask the LORD, He will show you what you are asking. It's all over the OT.
Enoch the prophet, the seventh from Adam, was shown all things written in the tablets of heaven, from the beginning of creation into the New Creation (which will begin after the 7,000 year millennial week of creation), and Enoch then wrote of them.
His writings lay the foundations of every doctrine used by all the holy prophets after him, from Genesis to Revelation, and for the reason that the foundations were laid down, those after him do not re-lay the foundations of what was, is, and is to come. Even our LORD and Savior was shown to Enoch, hidden with God, as God, in mystery, and who was to come, and in whose revealed name the righteous would be saved (who call on His revealed name).
In Enoch chapter 50, the prophet Enoch writes of the rapture and the change to the glory of the righteous before the tribulation, which will yet come.
From Moses' revelation of the Living Oracles, which were committed to the namesake people of the New Man Name of the One New Man/our Firstborn (and father by adoption into His name) so as to be a "show and tell" for the Person and work of the Firstborn who was to come and be our Redeemer, and then, on to the last book, the "Revelation of Jesus Christ", the prophets wrote of the Redeemer/Kinsman who would come (and is come, and shall come), and in whose name and by His once for all atonement the righteous would be redeemed.
And yes indeed, the rapture is in the OT, and in the NT, and Enoch first wrote of it it.
I have threads and posts on this forum in which I lay out the Scriptures that make mention of that by the prophets after Enoch, beginning with Moses.
In Leviticus 8, the garments made for beauty and for glory, which the baptized priests don which represent our new man flesh bodies of adoption, before they can enter the temple and be shut in for a seven day consecration period , are a "show and tell" of the entering into our chambers and being shut in, behind the temple in heaven's doors, when the LORD comes out of His place to judge the earth, but gathers His people unto Himself at the doors of heaven, to enter in and be hidden/shut in..
Isaiah 26: 19-21 Thy dead men shall live, together with my dead body shall they arise. Awake and sing, ye that dwell in dust: for thy dew is as the dew of herbs, and the earth shall cast out the dead.
Come, my people, enter thou into thy chambers, and shut thy doors about thee: hide thyself as it were for a little moment, until the indignation be overpast.
For, behold, the LORD cometh out of his place to punish the inhabitants of the earth for their iniquity: the earth also shall disclose her blood, and shall no more cover her slain.
Psalm 50:3-5 Our God shall come, and shall not keep silence: a fire shall devour before him, and it shall be very tempestuous round about him.
He shall call to the heavens from above, and to the earth, that he may judge his people.
Gather my saints together unto me; those that have made a covenant with me by sacrifice.
Psalm 75:2 when I receive/laqach=rapture! the congregation, I will judge (vindicate) uprightly (with perfect justice).
Psalm 75: 3 The earth and all the inhabitants thereof are dissolved ( hearts faint for fear of those things coming): I (will) bear up= reset the pillars of it. Selah.
So Enoch 50, Psalm 50, Isaiah26 and Psalm 75, for beginners, all tell of the rapture before the tribulation -which is to come.
Preface: I'm of the mind that there is no rapture. But I was wondering for those who believe in one, can you provide Old Testament proof that God or anyone else spoke of it? In Amos, it's said that God doesn't do anything except He reveal it to the prophets first. And please, if you're going to post, you can respond with something better than an abstract bit in Genesis where it's said that Enoch was taken up. OK? Thanks!