The bridegroom goes back to his father's house to prepare the bridal chamber, or closet. (bedroom) or chuppah (closet)
Joel mentions this bridal chamber in the context that everyone should fast in repentance before the Day of the Lord. Even people who would otherwise be feasting, such as a bride and groom. During the 30 days leading up to the Feast of Trumpets is a time for such fasting. During the Feast of Trumpets, it is a time for feasting again.
Gather the people, sanctify the congregation, assemble the elders, gather the children, and those that suck the breasts: let the bridegroom go forth of his chamber, and the bride out of her closet. Joel 2:16
Which is as a bridegroom coming out of his chamber [chuppah], and rejoiceth as a strong man to run a race. Psalm 19:5
The purpose of the chamber is privacy, because that is where intimacy takes place.
But it came to pass within a while after, in the time of wheat harvest, that Samson visited his wife with a kid; and he said, I will go in to my wife into the chamber. But her father would not suffer him to go in. Judges 15:1
Now there were men lying in wait, abiding with her in the . And she said unto him, The Philistines be upon thee, Samson. And he brake the withs, as a thread of tow is broken when it toucheth the fire. So his strength was not known. Judges 16:9
Delilah therefore took new ropes, and bound him therewith, and said unto him, The Philistines be upon thee, Samson. And there were liers in wait abiding in the chamber. And he brake them from off his arms like a thread. Judges 16:12
And Amnon said unto Tamar, Bring the meat into the chamber, that I may eat of thine hand. And Tamar took the cakes which she had made, and brought them into the chamber to Amnon her brother. And when she had brought them unto him to eat, he took hold of her, and said unto her, Come lie with me, my sister. 2 Samuel 13:10-11
And Bathsheba went in unto the king into the chamber: and the king was very old; and Abishag the Shunammite ministered unto the king. 1 Kings 1:15
More love in chambers from the Song of Solomon:
Draw me, we will run after thee: the king hath brought me into his chambers: we will be glad and rejoice in thee, we will remember thy love more than wine: the upright love thee. Song of Solomon 1:4
It was but a little that I passed from them, but I found him whom my soul loveth: I held him, and would not let him go, until I had brought him into my mother's house, and into the chamber of her that conceived me. Song of Solomon 3:4
It was understood to be the man's duty to go away to be with his father, build a house, or an addition on to the house, and prepare for the eventual wedding. Before he goes, though, he will make a statement to the bride, "I go to prepare a place for you; if I go, I will return again unto you."
In my Father's house are many mansions: if it were not so, I would have told you. I go to prepare a place for you. John 14:2
And if I go and prepare a place for you, I will come again, and receive you unto myself; that where I am, there ye may be also. John 14:3
As one can hide in a private chamber, so too, will those in the pre rapture be hid in heaven.
But the rest fled to Aphek, into the city; and there a wall fell upon twenty and seven thousand of the men that were left. And Benhadad fled, and came into the city, into an inner chamber. 1 Kings 20:30
And Micaiah said, Behold, thou shalt see in that day, when thou shalt go into an inner chamber to hide thyself. 1 Kings 22:25
The temple had a secret and/or inner chamber.
Who opposeth and exalteth himself above all that is called YAHVEH יהוה, or that is worshipped; so that he as YAHVEH יהוה sitteth in the temple of YAHVEH יהוה, shewing himself that he is YAHVEH יהוה. 2 Thessalonians 2:4
Wherefore if they shall say unto you, Behold, he is in the desert; go not forth: behold, he is in the secret chambers; believe it not. Matthew 24:26
Then David gave to Solomon his son the pattern of the porch, and of the houses thereof, and of the treasuries thereof, and of the upper chambers thereof, and of the inner parlours thereof, and of the place of the mercy seat, 1 Chronicles 28:11
Now when these things were thus ordained, the priests went always into the first tabernacle, accomplishing the service of YAHVEH יהוה. Hebrews 9:6
But into the second went the high priest alone once every year, not without blood, which he offered for himself, and for the errors of the people: Hebrews 9:7
The temple and tabernacle are both a pattern & picture of heaven, YAHVEH יהוה dwells in both.
Whoso therefore shall swear by the altar, sweareth by it, and by all things thereon.
And whoso shall swear by the temple, sweareth by it, and by him that dwelleth therein.
And he that shall swear by heaven, sweareth by the throne of YAHVEH יהוה, and by him that sitteth thereon. Matt 23:20-22
It was therefore necessary that the patterns of things in the heavens should be purified with these; but the heavenly things themselves with better sacrifices than these. Hebrews 9:23
For Christ is not entered into the holy places made with hands, which are the figures of the true; but into heaven itself, now to appear in the presence of YAHVEH יהוה for us: Hebrews 9:24
Hiding in the temple is also mentioned in scripture. From what I have just shown, it can be seen that this is a metaphor for being hid in heaven during the time of trouble, or tribulation.
For in the time of trouble he shall hide me in his pavilion: in the secret of his tabernacle shall he hide me; he shall set me up upon a rock. Psalm 27:5
Furthermore, this is a quote from Psalm 27, which is to be read every day for the 30 days leading up to the Feast of Trumpets, also known as the Wedding of the Messiah. Also, Psalm 27 contains other rapture parallels and language. Take a moment to read it and see for yourself.
Thou shalt hide them in the secret of thy presence from the pride of man: thou shalt keep them secretly in a pavilion from the strife of tongues. Psalm 31:20
Understanding the purpose and symbolic meaning of the chambers, that they represent heaven, shows that these verses from Isaiah are talking about the pre tribulation rapture to heaven.
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. Isaiah 26:19-21
In that day the LORD with his sore and great and strong sword shall punish leviathan the piercing serpent, even leviathan that crooked serpent; and he shall slay the dragon that is in the sea. Isaiah 27:1