New Revised Standard Version
For this reason God sends them a powerful delusion, leading them to believe what is false,

Contemporary English Version
So God will make sure they are fooled into believing a lie.

New American Bible
Therefore, God is sending them a deceiving power so that they may believe the lie,

Douay-Rheims Bible
That all may be judged who have not believed the truth but have consented to iniquity.

That all may be judged who have not believed the truth but have consented to iniquity.

for.

Psalm 81:11,12 But my people heard not my voice: and Israel hearkened not to me. . . .

Psalm 109:17 But persecuted the poor man and the beggar; and the broken in heart, to put him to death.

Isaiah 29:9-14 Be astonished, and wonder, waver, and stagger: be drunk, and not with wine: stagger, and not with drunkenness. . . .

John 12:39-43 Therefore they could not believe, because Isaias said again: . . .

Romans 1:21-25,28 Because that, when they knew God, they have not glorified him as God or given thanks: but became vain in their thoughts. And their foolish heart was darkened. . . .

God.

1 Kings 22:18-22 (Then the king of Israel said to Josaphat: Did I not tell thee, that he prophesieth no good to me, but always evil?) . . .

2 Chronicles 18:18-22 Then he said: Hear ye therefore the word of the Lord: I saw the Lord sitting on his throne, and all the army of heaven standing by him on the right hand and on the left, . . .

See on

Isaiah 6:9,10 And he said: Go, and thou shalt say to this people: Hearing, hear, and understand not: and see the vision, and know it not. . . .

Ezekiel 14:9 And when the prophet shall err, and speak a word: I the Lord have deceived that prophet: and I will stretch forth my hand upon him, and will cut him off from the midst of my people Israel.

that.

Isaiah 44:20 Part thereof is ashes: his foolish heart adoreth it, and he will not save his soul, nor say: Perhaps there is a lie in my right hand.

Isaiah 66:4 Wherefore I also will choose their mockeries, and will bring upon them the things they feared: because I called, and there was none that would answer; I have spoken, and they heard not; and they have done evil in my eyes, and have chosen the things that displease me.

Jeremiah 27:10 For they prophesy lies to you: to remove you far from your country, and cast you out, and to make you perish.

Ezekiel 21:29 Whilst they see vain things in thy regard, and they divine lies: to bring thee upon the necks of the wicked that are wounded, whose appointed day is come in the time of iniquity.

Matthew 24:5,11 For many will come in my name saying, I am Christ. And they will seduce many. . . .

1 Timothy 4:1 Now the Spirit manifestly saith that in the last times some shall depart from the faith, giving heed to spirits of error and doctrines of devils,