There are contradictions of Islam, if a person falls into them consciously and by choice, they take him out of Islam, God forbid. Scientists have compiled them into ten great things to watch out for.

Ten contradictions of Islam
1. Polytheism by God

Such as praying to someone other than Allah, slaughtering someone else, or asking for help from the Guardians.

2. Taking the arguments between the slave and his Lord

As someone who calls someone other than God to draw him closer to God.

3. Disbelieving polytheists or doubting their disbelief

Or correct their doctrine.

4. The belief that a guide other than the Prophet (peace and blessings of Allaah be upon him) is more complete than a gift
5. No matter what the Prophet (peace and blessings of Allaah be upon him) said
6. Mocking something of God's religion, reward or punishment

Come on, he said:
Say I respect Allah, His signs and His Messenger, you were mocking, do not apologize, you have disbelieved after your faith (repentance: 65-66)

7. Magic
8. The demonstration of polytheists and their help to Muslims
9. The belief that some people can deviate from the Islamic law
10. Dissenting from the religion of God and not learning or working with it
Important notice

It is not permissible to judge people for Kufr only by the people of knowledge and the Sharia judiciary, because Kufr has great rules in Islam.