Question:
Is it permissible for Muslims to exchange greetings with Christians on every occasion?
Answer:
It is not permissible to greet Christians or other disbelievers on their festivals and religious occasions, for this will be a sort of encouraging them in their falsehood and sharing in their sin. Allah, the Exalted, states, “…but do not help one another in sin and transgression.” [al-Maidah: 2]
However, the prohibition may be lifted if there is an interest, which will most likely be achieved and is required by Purified Shari’ah (Islamic Law).