Assalamualaikum. There is no doubt that any person who boasts about sin and consider that particular sin permissible, is a kaffir. But what about that sort of person who brags about his sins, but at the same time in his heart he considers those sins and bragging about as impermissible too. My understanding is that the latter one would not be deem kaafir, because there is no disbelief. Please enlighten me.
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
It is established in the methodology of Ahlus-Sunnah that a person does not go out of the fold of Islam by committing a sin until he considers it lawful.
Just committing a sin, or committing it openly, or even boasting about it while believing that it is forbidden and that one deserves punishment for doing it, is not regarded as making it lawful; the matter which renders a person out of the fold of Islam.
However, the person who commits such a sin is upon a grave danger, and his act reflects that he is severely hard-hearted, we seek refuge in Allah from this.
Allah knows best.
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