post-Christian       
adjective uk/ˌpəʊstˈkrɪs.tʃən/ /ˌpəʊstˈkrɪs.ti.ən/ us/ˌpoʊstˈkrɪs.tʃən/
 后基督教
relating to a period or society in which Christianity has stopped being the main religion
  He contends that we live in a post-Christian age. 他认为我们生活在后基督教时代。 
 This is a secular society that some intellectuals have described as post-Christian.
 - More examples
 - Post-Christian religious traditions are discussed in the final chapters of the book.
 - Her fellow Christians, she suggests, need to understand that they will soon be living in a post-Christian country.
 - It's not a post-Christian society, but a place where religiously informed moral judgment is very much a part of public life.