2 Thessalonians 2:11

And because of this God will send them the force of a delusion, for them to believe a lie,

Romans 1:28

And just as they did not approve having God in knowledge, God gave them over to an unfit mind, to do things that are not fit;

Ezekiel 14:9

And if the prophet is deceived and speaks a word, I, LORD, have deceived that prophet. And I will stretch out my hand upon him, and will destroy him from the midst of my people Israel.

1 Kings 22:18-22

And the king of Israel said to Jehoshaphat, Did I not tell thee that he would not prophesy good concerning me, but evil?

2 Chronicles 18:18-22

And [Micaiah] said, Therefore hear ye the word of LORD. I saw LORD sitting upon his throne, and all the host of heaven standing at his right hand and at his left.

Psalm 81:11-12

But my people hearkened not to my voice, and Israel would none of me.

Psalm 109:17

Yea, he loved cursing, and it came to him. And he did not delight in blessing, and it was far from him.

Isaiah 6:9-10

And he said, Go, and tell this people, Hear ye indeed, but do not understand, and see ye indeed, but do not perceive.

Isaiah 29:9-14

Tarry ye and wonder, take your pleasure and be blind. They are drunken, but not with wine. They stagger, but not with strong drink.

Isaiah 44:20

He feeds on ashes. A deceived heart has turned him aside. And he cannot deliver his soul, nor say, Is there not a lie in my right hand?

Isaiah 66:4

I also will choose their delusions, and will bring their fears upon them. Because when I called, none answered. When I spoke, they did not hear. But they did that which was evil in my eyes, and chose that in which I did not delight

Jeremiah 27:10

For they prophesy a lie to you, to remove you far from your land, and that I should drive you out, and ye should perish.

Ezekiel 21:29

while they see for thee FALSE visions, while they divine lies to thee, to lay thee upon the necks of the wicked who are deadly wounded, whose day has come in the time of the iniquity of the end.

Matthew 24:5

For many will come in my name, saying, I am the Christ, and will lead many astray.

Matthew 24:11

And many FALSE prophets will arise, and will lead many astray.

John 12:39-43

Because of this they could not believe. Because Isaiah said again,

Romans 1:21-25

Because, although knowing God, they did not glorify him as God, nor were they thankful, but became vain in their reasonings and their heart was darkened without understanding.

1 Thessalonians 2:3

For our exhortation is not from error, nor from uncleanness, nor in deception,

1 Timothy 4:1

But the Spirit says expressly that in latter times some will depart from the faith, giving heed to deceitful spirits and doctrines of demons,

Treasury of Scripture Knowledge

Summary

And for this cause God shall send them strong delusion, that they should believe a lie:

Bible References

General references

Exodus 8:7
And the magicians did in like manner with their enchantments, and brought up frogs upon the land of Egypt.
Exodus 10:20
But LORD hardened Pharaoh's heart, and he did not let the sons of Israel go.
Leviticus 13:29
And when a man or woman has a disease upon the head or upon the beard,
Deuteronomy 13:2
and the sign or the wonder comes to pass, of which he spoke to thee, saying, Let us go after other gods, which thou have not known, and let us serve them,
Deuteronomy 28:28
LORD will smite thee with madness, and with blindness, and with confusion of mind,
Deuteronomy 29:4
yet LORD has not given you a heart to know, and eyes to see, and ears to hear, to this day.
Psalm 109:17
Yea, he loved cursing, and it came to him. And he did not delight in blessing, and it was far from him.
Isaiah 47:12
Stand now with thine enchantments, and with the multitude of thy sorceries, in which thou have labored from thy youth, if so be thou shall be able to profit, if so be thou may prevail.