If someone has a wrong understanding of Islam and teaches it and a Muslim is there and knows that it is wrong but does not say anything, has he commented Kufr (disbelief)?
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, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
A Muslim does not commit Kufr by merely remaining silent regarding this matter. However, if it concerns knowledge that is obligatory to be taught, then withholding it is a grave misdeed. It is impermissible to withhold such knowledge; rather, he must speak, otherwise he bears a sin for withholding it. Allah, The Exalted, says (what means): {Indeed, those who conceal what We sent down of clear proofs and guidance after We made it clear for the people in the Scripture - those are cursed by Allah and cursed by those who curse.} [Quran 2:159]
Abu Hurayrah reported that the Prophet, sallallaahu ‘alayhi wa sallam, said, “Whoever is asked about knowledge and conceals it will be bridled with reins of fire on the Day of Resurrection.” [Abu Daawood]
Al-Khattaabi commented on the hadeeth, saying:
“This hadeeth applies to the knowledge whose acquisition is obligatory on Muslims. For instance, if a non-Muslim wants to embrace Islam and asks Muslims to teach him about Islam and how to perform the prayer or if a Muslim asks about the permissibility of an action, then they must be answered, and the one being asked such questions cannot withhold his knowledge in these situations. If he withholds knowledge, he is subjected to the stern warnings and promised punishment for that. This ruling does not apply to secondary branches of knowledge which people are not obliged to learn.”
Allah knows best.
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