It is narrated from Usama bin Zaid, may Allah be pleased with him, that the Messenger of Allah, peace and blessings be upon him, passed by a gathering in which Muslims, idol-worshipping polytheists, and Jews were sitting, so he, peace and blessings be upon him, greeted them with salam. Agreed upon.
Hadith Referenceمشكوة المصابيح / كتاب الآداب / 4639
Hadith Gradingالألبانی:مُتَّفق عَلَيْهِ | زبیر علی زئی:متفق عليه
Hadith Takhrij´تحقيق و تخريج: محدث العصر حافظ زبير على زئي رحمه الله` «متفق عليه، رواه البخاري (2654) و مسلم (116/ 1798)»