You mean, specifically Christianity? Even though I am repeatedly implying all religious groups?

"ethnic group" was poor wording and should have just used "group", sorry I'm not English native. I do NOT support nationalism of global religions. The phrase is used by some religious people to call themselves that, I guess that's why I confused it:

An ethnoreligious group (or an ethno-religious group) is a group of people with a common religious and ethnic background[1] or, in some cases, a religious background exclusively.[2][3]

Read citations if you want: https://en.wikipedia.org/wiki/Ethnoreligious_group