Sayyidah Aishah (may Allah be pleased with her) narrated from the Messenger of Allah (peace and blessings be upon him) that the Messenger of Allah (peace and blessings be upon him) said: "The Muslims are bound by their conditions, insofar as they agree with the truth."
(b) Anas bin Malik (may Allah be pleased with him) said that the Messenger of Allah (peace and blessings be upon him) said: "The Muslims are bound by their conditions, those of them that agree with the truth."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصداق / 14435