Itadakimasu
If you didn’t already know about Japanese etiquette, you should really read up on it if you plan on visiting the island country. Small things like gestures, facial expressions, and verbal expressions can be huge. For instance, if you’re dining out with a group of friends and someone hands you something to eat. What do you do?
The common thing to say when you receive food or drink from a host is, “Itadakimasu,” which basically translates into, “I humbley receive.” This is a cultural thing, not a religious one. However, someone might also ask that everyone hold hands and say it together, which might be a religious thing.