And because of this, God will send them a working of error for them to believe the lie in order that they should be judged, all who do not believe in the truth but take pleasure in unrighteousness, 2 Thessalonians 2:11–12.
After the rapture of the Church, no more believers will be added to it. Although God will still work out salvation for many during the Tribulation period, this salvation will not be based upon the promises and possession belonging to the Church. We are approaching two thousand years since the resurrection of Christ, and the message of His resurrection is well known in every nation. When the man of lawlessness comes—the beast of Revelation—those who have rejected the truth will be caused to accept the lie proclaimed by him so that they fall into judgement.
This lie is independence from God—the very same lie Satan employed in his first attack on humanity in the Garden against Eve. He is the father of the lie (John 8:44). All who follow and worship the beast in this lie will be cast into Gehenna when Christ returns to establish His kingdom, for they will receive no mercy because of their rejection of the truth and their love of unrighteousness (Revelation 14:9–11).