How must a Muslim person treat his parents if they are Murtad?

Answer:

(Fatwa: 252-252=L)

If parents of a Muslim turn murtad (apostate) he should neither have a relation with them nor eat or drink with them:

ولاترکنوا الی الذین ظلموا فتمسکم النار الآیہ وفی الکشاف: والنہی متناول لہ الخطاط والانقطاع الیہم ومصاحبتہم ومجالستہم الخ (الکشاف:۲/۲۹۶)

Allah (Subhana Wa Ta’ala) knows Best

Darul Ifta,
Darul Uloom Deoband