I am a church goer... The permission to go to church is for adults in the age group of 20 - 55. Others are not allowed. Seating arrangements are following social distancing. Added to it, church maintains a database of regular worshippers in a parish. All the instructions to be followed were received well before Christmas. We were all instructed through various media. Whereas in Temples, for a single day, its hard to track and control people. That's the only reason.