Answered by Ustadh Salman Younas
Question: Is it permissible to reply to a non-Muslim’s sneeze with “Bless you”? It is common practice in the West. Many non-Muslims consider it a kind gesture, especially if they already have a habit of saying it to you when you sneeze. Does the ruling change for a Muslim?
Answer: assalamu `alaykum
There is absolutely nothing wrong with such a practice regardless of whether it is said in response to a non-Muslim or Muslim.
The phrase “bless you” has become a largely customarily response to someone who sneezes. Even if consciously intended as a supplication, our tradition does not prohibit such a supplication for a non-Muslim. Rather, it is established in the primary texts that the Prophet (God bless him and grant him peace) supplicated for non-Muslims. For more details, please refer to:
Additionally, it cannot be said that responding to someone in this manner is “imitating” the practice of non-Muslims and therefore impermissible. This is because the “imitation” that is prohibited in our tradition is a very specific sort, namely one that is done with the keen resolve to be like non-Muslims and/or in those aspects that are clearly impermissible or so specific to non-Muslims that an onlooker would consider you to be among them when witnessing you partaking in such actions. [Ibn Abidin, Hashiya; Taqi Usmani, Taqrir al-Tirmidhi]
In light of the above, saying bless you in response to someone sneezing is not impermissible because it is largely viewed as a customary practice among people that is not specific to a particular religious tradition, and even if intended as a supplication, it does not contradict the principles and rulings of our tradition. In fact, given that we are called upon to act with others in a positive, respectful, and courteous manner, uttering such a response with the intention of fulfilling these dictates of our tradition would make the act rewarding.
Checked & Approved by Shaykh Faraz Rabbani