In the context of 1Thes 5:9, when does this wrath of God take place?
1Th 5:2 For yourselves know perfectly that the day of the Lord so cometh as a thief in the night.
1Th 5:3 For when they shall say, Peace and safety; then sudden destruction cometh upon them, as travail upon a woman with child; and they shall not escape.
1Th 5:4 But ye, brethren, are not in darkness, that that day should overtake you as a thief.
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1Th 5:9 For God hath not appointed us to wrath, but to obtain salvation by our Lord Jesus Christ,
When does the sudden destruction come? It comes in the day of the Lord. The day of the Lord is the most spoken of event in the Scriptures. It is within this period of time that God's eschatological wrath is poured out upon the unbelieving, Beast worshiping, earth dwellers. Two prominent themes of this period are God's vengeance and recompense. He will recompense the unbelievers who have persecuted His own unto death with vengeance.
Isa 34:8 For it is the day of the LORD'S VENGEANCE, and the year of RECOMPENCES for the controversy of Zion.
Isa 35:4 Say to them that are of a fearful heart, Be strong, fear not: behold, your God will come with VENGEANCE, even God with a RECOMPENCE; he will come and save you.
2Th 1:6 Seeing it is a righteous thing with God to RECOMPENSE tribulation to them that trouble you;
2Th 1:7 And to you who are troubled rest with us, when the Lord Jesus shall be revealed from heaven with his mighty angels,
2Th 1:8 In flaming fire taking VENGEANCE on them that know not God, and that obey not the gospel of our Lord Jesus Christ:
2Th 1:9 Who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power;
2Th 1:10 When he shall come to be glorified in his saints, and to be admired in all them that believe (because our testimony among you was believed) in that day.
It is God's recompense of vengeance in the day of the Lord that we are not appointed unto.
When does the day of the Lord take place? When does the wrath of God take place? The eschatological wrath of God takes place in the period known as the day of the Lord.
Joel the prophet and Peter quoting Joel (Acts 2:20), both said that the day of the Lord comes after a specific cosmic sign.
Joe 2:31 The sun shall be turned into darkness, and the moon into blood, before the great and the terrible day of the LORD come.
The cosmic sign comes before the day of the Lord and God's recompense of vengeance therein.
John describes this very cosmic sign when the sixth seal was opened.
Rev 6:12 And I beheld when he had opened the sixth seal, and, lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood;
Rev 6:13 And the stars of heaven fell unto the earth, even as a fig tree casteth her untimely figs, when she is shaken of a mighty wind.
Rev 6:14 And the heaven departed as a scroll when it is rolled together; and every mountain and island were moved out of their places.
Rev 6:15 And the kings of the earth, and the great men, and the rich men, and the chief captains, and the mighty men, and every bondman, and every free man, hid themselves in the dens and in the rocks of the mountains;
Rev 6:16 And said to the mountains and rocks, Fall on us, and hide us from the face of him that sitteth on the throne, and from the wrath of the Lamb:
Rev 6:17 For the great day of his wrath is come; and who shall be able to stand?
If the cosmic sign doesn't take place until the events associated with the opening of the sixth seal, then the eschatological wrath of God in the day of the Lord doesn't take place until after the events of the sixth seal.
It is this cosmic sign and the effects of the great earthquake ("the sea and the waves roaring") associated with it that Christ says, when we see them, that we are to be encouraged ("lift up your heads") and look to the sky for Christ will appear at any moment to complete our redemption. Notice the fearfulness of men and the distress of the nations with perplexity. Is it not describing the same hiding in fear that John witnessed in Rev 6:15-16 and Isaiah prophesied of as presented below?
Luk 21:25 And there shall be signs in the sun, and in the moon, and in the stars; and upon the earth distress of nations, with perplexity; the sea and the waves roaring;
Luk 21:26 Men's hearts failing them for fear, and for looking after those things which are coming on the earth: for the powers of heaven shall be shaken.
Luk 21:27 And then shall they see the Son of man coming in a cloud with power and great glory.
Luk 21:28 And when these things begin to come to pass, then look up, and lift up your heads; for your redemption draweth nigh.
Isa 2:19 And they shall go into the holes of the rocks, and into the caves of the earth, for fear of the LORD, and for the glory of his majesty, when he ariseth to shake terribly the earth.
The wrath of God that we are not appointed unto doesn't take place until after the cosmic sign that John witnessed at the opening of the sixth seal. All these descriptions of the wrath of God happen after the cosmic sign. So, when does the great tribulation take place in relation to the cosmic sign? Jesus tells us in Matt 24:29.
Mat 24:29 Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:
Mat 24:30 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.
Mat 24:31 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.
Jesus says the notable cosmic sign happens immediately after the tribulation of those days. The days of tribulation in the context are those of the great tribulation as mentioned in verses 21-22.
Mat 24:21 For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.
Mat 24:22 And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened.
So, the question is: Is the great tribulation the period of God's eschatological wrath? It cannot be, for it is over when the precursor sign of the day of the Lord takes place.
The church will be caught away before the wrath of God in the day of the Lord which comes after the church has suffered persecution at the hand of the Beast. Please note that the trumpet and bowl judgments are the expressions of God's eschatological wrath in the day of the Lord, they do not take place within the period of unprecedented persecution of the elect that Jesus called the great tribulation.
May our gracious Lord bless you with full understanding.