Christian Church Etiquette

Photo by Vincent Ciro https://pixabay.com/en/users/VinnyCiro-219264/

• Take off shoes in some churches.
  In Ethiopia, for instance, visitors are expected to take their shoes off. In American churches, though, that's not usually the case.
• Cover your shoulders and knees.
  It's polite to avoid wearing a sleeveless top or short shorts. Bring a sweater or shawl to cover up, and wear knee-length pants and skirts.
• Ask permission before taking pictures.
  Some Italian churches don't allow cameras at all, so check first before taking pictures or filming.
• Don't cross your legs.
  When seated in Greek Orthodox churches, refrain from crossing your legs.

original source: http://www.bbc.com/travel/blog/20110616-travelwise-religious-tourism-etiquette