Narrated AbuHurayrah: The Prophet (ﷺ) said: Conciliation between Muslims is permissible. The narrator Ahmad added in his version: "except the conciliation which makes lawful unlawful and unlawful lawful." Sulayman ibn Dawud added: The Messenger of Allah (ﷺ) said: Muslims are on (i.e. stick to) their conditions

English translation · Sunan Abu Dawud