The rapture is a post trib rapture.
It is clearly at the coming of the Lord.
Christ comes back only a second time, not 3, 4 times.
1 Thessalonians 4:15-17New King James Version (NKJV)
15 For this we say to you by the word of the Lord, that we who are alive and remain until the coming of the Lord will by no means precede those who are asleep. 16 For the Lord Himself will descend from heaven with a shout, with the voice of an archangel, and with the trumpet of God. And the dead in Christ will rise first.17 Then we who are alive and remain shall be caught up together with them in the clouds to meet the Lord in the air. And thus we shall always be with the Lord.
This passage is universally thought of as the 'rapture event' and clearly this happens at the second coming of the Lord.
And fully agrees with Christ in Matthew 24 saying
The Coming of the Son of Man
29 “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. 30 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. 31 And He will send His angels with a great sound of a trumpet, and they will gather together His elect from the four winds, from one end of heaven to the other.
Do you all see the trumpet connection here?
Well with so many trumpets that will sound during Daniel's 70th week (the Tribulation), there's no need to verify which trumpet Paul spoke of in 1 Thessalonians 4:15-17 as long as the word trumpet is found in a text it must be a post-tribulation rapture.
Isaiah 27:12-13 New King James Version (NKJV)
12 And it shall come to pass in that day
That the Lord will thresh,
From the channel of the River to the Brook of Egypt;
And you will be gathered one by one,
O you children of Israel.
13 So it shall be in that day:
The great trumpet will be blown;
They will come, who are about to perish in the land of Assyria,
And they who are outcasts in the land of Egypt,
And shall worship the Lord in the holy mount at Jerusalem.
Jeremiah 51:27 New King James Version (NKJV)
Set up a banner in the land,
Blow the trumpet among the nations!
Prepare the nations against her,
Call the kingdoms together against her:
Ararat, Minni, and Ashkenaz.
Appoint a general against her;
Cause the horses to come up like the bristling locusts.
Joel 2:1 New King James Version (NKJV)
Blow the trumpet in Zion,
And sound an alarm in My holy mountain!
Let all the inhabitants of the land tremble;
For the day of the Lord is coming,
For it is at hand:
Joel 2:15-17 New King James Version (NKJV)
15 Blow the trumpet in Zion,
Consecrate a fast,
Call a sacred assembly;
16 Gather the people,
Sanctify the congregation,
Assemble the elders,
Gather the children and nursing babes;
Let the bridegroom go out from his chamber,
And the bride from her dressing room.
17 Let the priests, who minister to the Lord,
Weep between the porch and the altar;
Let them say, “Spare Your people, O Lord,
And do not give Your heritage to reproach,
That the nations should rule over them.
Why should they say among the peoples,
‘Where is their God?’”
Zephaniah 1:14-17 New King James Version (NKJV)
14 The great day of the Lord is near;
It is near and hastens quickly.
The noise of the day of the Lord is bitter;
There the mighty men shall cry out.
15 That day is a day of wrath,
A day of trouble and distress,
A day of devastation and desolation,
A day of darkness and gloominess,
A day of clouds and thick darkness,
16 A day of trumpet and alarm
Against the fortified cities
And against the high towers.
17 “I will bring distress upon men,
And they shall walk like blind men,
Because they have sinned against the Lord;
Their blood shall be poured out like dust,
And their flesh like refuse.”
Zechariah 9:9-16 New King James Version (NKJV)
9 “Rejoice greatly, O daughter of Zion!
Shout, O daughter of Jerusalem!
Behold, your King is coming to you;
He is just and having salvation,
Lowly and riding on a donkey,
A colt, the foal of a donkey.
10 I will cut off the chariot from Ephraim
And the horse from Jerusalem;
The battle bow shall be cut off.
He shall speak peace to the nations;
His dominion shall be ‘from sea to sea,
And from the River to the ends of the earth.
11 “As for you also,
Because of the blood of your covenant,
I will set your prisoners free from the waterless pit.
12 Return to the stronghold,
You prisoners of hope.
Even today I declare
That I will restore double to you.
13 For I have bent Judah, My bow,
Fitted the bow with Ephraim,
And raised up your sons, O Zion,
Against your sons, O Greece,
And made you like the sword of a mighty man.”
14 Then the Lord will be seen over them,
And His arrow will go forth like lightning.
The Lord God will blow the trumpet,
And go with whirlwinds from the south.
15 The Lord of hosts will defend them;
They shall devour and subdue with slingstones.
They shall drink and roar as if with wine;
They shall be filled with blood like basins,
Like the corners of the altar.
16 The Lord their God will save them in that day,
As the flock of His people.
For they shall be like the jewels of a crown,
Lifted like a banner over His land—
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