6 But this you have in your favour, that you hate the deeds of the Nicolaitans, which I also hate.
Revelation 2:6 Cross References - RKJNT
2 John 1:9-10
Revelation 2:14-15
14 But I have a few things against you, because you have there those who hold to the teaching of Balaam, who taught Balak to cast a stumbling block before the sons of Israel, that they might eat things sacrificed to idols, and commit sexual immorality.
15 In the same way you also have those who hold to the teachings of the Nicolaitans.