Now that you mention that. Heres a list Ive gotten from different sources who warn about cults and what to look for.
Signs of a cult.
1. They replace Christ --- Vicar of Christ
2. cult teachers will proclaim a "gospel message" that is ultimately is a message of works-centered salvation, in sharpest contrast to the Good News of saving grace through faith in Christ (Ephesians 2:8-9). They'll preach "another gospel."
3. the revealed spiritual nature of the work of the cult claims to be, but actually is not, inspired by God the Spirit. Instead, a chilling reference is made to spiritual entities who lend tremendous spiritual power to their natural human puppets to preach deceptive gospels. They'll be empowered by "another spirit." This is the work of demonic agents in allegiance with Satan, the opposer of God throughout history.
4. Has a leader that is revered by cult members.
5. The leader claims special authority
6. Divine Revelation claimed by the leader which is non-verifiable.
7. Usually changes and/or evolves over time.
8. Intolerant members cannot challenge or even question cult doctrine or decisions made by cult leadership.
9. Overrriding authority (i.e. correcting, amending or even replacing the Bible) attributed to the special divine revelation.
10. Denial of the authority and completeness of Scripture
11. Signs, signals or other means of identification and/or recognition
12. Dressing differently, sometimes in special uniforms or costumes.
How many of those can be applied to the RCC?
Titus 3:9 but avoid foolish questions, and genealogies, and contentions, and strivings about the law. For they are unprofitable and vain.
Titus 3:10 A man that is a heretic, after the first and second admonition, avoid:
Titus 3:11 Knowing that he, that is such an one, is subverted, and sinneth, being condemned by his own judgment.
Those who continue to deny the deity of Christ can fool themselves however they like, but they should get used to the idea of hearing, "I never knew you" from the very Jesus Christ they deny is God.
ALL OF THEM. And add: They claim there is no salvation outside their religion. That they are the only way to God.