Sahih Bukhari

Narrated `Abdullah bin `Amr:The Prophet (ﷺ) said, ""Al-Ka`ba'ir (the biggest sins) are: To join others (as partners) in worship with Allah, to be undutiful to one's parents,"" or said, ""to take a false oath."" (The sub-narrator, Shu`ba is not sure) Mu`adh said: Shu`ba said, ""Al-Ka`ba'ir (the biggest sins) are: (1) Joining others as partners in worship with Allah, (2) to take a false oath (3) and to be undutiful to one's parents,"" or said, ""to murder (someone unlawfully)