No one knows when the great day will be, not the angels, not even the Son, at least in the days of His incarnation, Matthew 24.36, Acts 1.7, but we do know two things:
what will happen, and
how to be ready.
What will happen? There are a lot of schedules taught in Christendom about the last things. So, to simplify the matter, let’s only take the one Greek word parousia, translated “coming.”
At the parousia, Christ will be revealed – the revelation.
2Thes 2:1 Now we request you, brethren, with regard to the coming of our Lord
2Thes 1:7 … when the Lord Jesus will be revealed from heaven with His mighty angels in flaming fire
At the parousia, Christ will raise the dead – the resurrection.
1Thes 4:15 … we who are alive and remain until the coming of the Lord, will not precede those who have fallen asleep.
1Thes 4:16 For the Lord Himself will descend from heaven with a shout, with the voice of the archangel and with the trumpet of God, and the dead in Christ will risefirst.
See also: 1Cor 15.22,23
At the parousia, Christ will “catch up” the believers who are then alive – the rapture.
1Thes 4:15 … we who are alive and remain until the coming of the Lord, will not precede those who have fallen asleep.
1Thes 4:17 Then we who are alive and remain will be caughtup together with them in the clouds to meet the Lord in the air, and so we shall always be with the Lord.
See also: 1Cor 15.52
At the parousia, Christ will gather to Himself all believers of all times.
2Thes 2:1 Now we request you, brethren, with regard to the coming of our Lord Jesus Christ and our gathering together to Him
1Thes 4:17 Then we who are alive and remain will be caught up together with them in the clouds to meet the Lord in the air, and so we shall always be with the Lord.
At the parousia, Christ will judge – it will be the judgment day.
2Thes 2:1 Now we request you, brethren, with regard to the coming of our Lord Jesus Christ and our gathering together to Him,
2Thes 1:8, 9 dealing out retribution to those who do not know God and to those who do not obey the gospel of our Lord Jesus. These will pay the penalty of eternal destruction, away from the presence of the Lord and from the glory of His power
At the parousia, Christ will destroy everything – souls and bodies of unbelievers will be thrown into hell, Matt 10.28, and it will be the end of heaven and earth.
2Thes 2:1 Now we request you, brethren, with regard to the coming of our Lord Jesus Christ and our gathering together to Him,
2Thes 1:8, 9 dealing out retribution to those who do not know God and to those who do not obey the gospel of our Lord Jesus. These will pay the penalty of eternal destruction, away from the presence of the Lord and from the glory of His power
2Peter 3:12 looking for and hastening the coming of the day of God, because of which the heavens will be destroyed by burning, and the elements will melt with intense heat
At the parousia, Christ will end it all.
Mat 24:3 … what will be the sign of Your coming, and of the end of the age?
1Cor 15:23, 24 But each in his own order: Christ the first fruits, after that those who are Christ’s at His coming, then comes the end, when He hands over the kingdom to the God
At the parousia, Christ will make all things new.
2Pet 3:12, 13 looking for and hastening the coming of the day of God, because of which the heavens will be destroyed by burning, and the elements will melt with intense heat! But according to His promise we are looking for newheavens and anewearth, in which righteousness dwells.