What is a Muslim's duty towards a non-Muslim, whether the non-Muslim is a dhimmi in a Muslim land, or the Muslim is residing in a non-Muslim land, concerning interactions ranging from offering greetings of peace to celebrating their holidays? And is it permissible to befriend them solely for work purposes?

A Muslim's duty towards a non-Muslim involves several matters:

Firstly: Inviting them to Islam by clarifying its truth, for the Prophet, peace and blessings be upon him, said: "Whoever guides to good will have a reward like that of its doer."

Secondly: Not wronging them in their person, property, or honor if they are a dhimmi, a musta'min (one who has been granted safe conduct), or one with whom a treaty has been made, but rather fulfilling their rights.

Thirdly: The permissibility of engaging in transactions with them, such as buying and selling. Indeed, the Prophet, peace and blessings be upon him, bought from Jews and died while his shield was mortgaged to a Jew.

Fourthly: Not initiating the greeting of salam, but responding with "wa alaikum" if they greet first.

Fifthly: Good neighborliness if they are a neighbor, by being kind to them, not harming them, and giving charity to them if they are poor, for the Prophet, peace and blessings be upon him, said: "Gabriel kept on enjoining good treatment of neighbors to the extent that I thought he would make them heirs."

Sixthly: Not participating in their holiday celebrations, but there is no harm in offering condolences for their deceased by saying: "May Allah mend your affliction," without supplicating for forgiveness or mercy for the deceased if they were a disbeliever. However, one may supplicate for guidance for the living.