2 Peter 2:15

They have left the straight road and gone astray. They have followed the road that Balaam, the son of Beor, trod, who fell in love with the profits of wrongdoing

Revelation 2:14

Yet I hold it somewhat against you that you have among you some who are clinging to the teaching of Balaam, who taught Balak to set a trap for the children of Israel, to entice them to eat the meat that had been sacrificed to idols and to commit immoral practices.

Treasury of Scripture Knowledge

Summary

Behold, these caused the children of Israel, through the counsel of Balaam, to commit trespass against the LORD in the matter of Peor, and there was a plague among the congregation of the LORD.

Bible References

These caused

2 Peter 2:15
They have left the straight road and gone astray. They have followed the road that Balaam, the son of Beor, trod, who fell in love with the profits of wrongdoing
Revelation 2:14
Yet I hold it somewhat against you that you have among you some who are clinging to the teaching of Balaam, who taught Balak to set a trap for the children of Israel, to entice them to eat the meat that had been sacrificed to idols and to commit immoral practices.