Responding to a Non-Muslim's greeting

[Amatullah]

also the opinion of most of the scholars and the majority of the salaf… It is permissible to initiate the greeting when addressed to a group composed of both Muslims and kaafirs, or one Muslim and a number of kaafirs, but he should intend the greeting to be directed towards the Muslim(s) among them, because the Prophet (peace and blessings of Allaah be upon him) greeted an assembly that included a mixture of Muslims and mushrikeen.

(Shaikh Muhammad Saleh al-Munajjid)

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