Answer:
(Fatwa: 312/286=B/1430)
The ithana ashri Shias, as per the false beliefs written in their books are out of folk of Islam. A Muslim should neither have close relations with them nor should have relation of eating and drinking. Yes, there is no wrong in having moral relations. A Muslim should not initiate salam to them, but if they greet they can be responded with wa’alaik (وعلیک).
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband
