Reference: Sharh ‘Umdatil-Fiqh – Tape No.4, Question No.49
Question: What is the ruling regarding initiating [the greeting of] as-salaam [‘alaykum] with the disbelievers, particularly if it is for the sake of da’wah?
Response: No, don’t initiate [the greeting of as-salaam ‘alaykum]. The Messenger ﷺ said:
«Do not initiate [the greeting of] as-salaam [‘alaykum] with the Jews and the Christians»
[So] how can we [then] ignore this hadeeth, and say [this is] for the sake of da’wah? No [we cannot].