irreligiousness

/ˌɪrɪˈlɪdʒəsnəs/
noun
  1. The quality or state of being without religious belief, practice, or reverence.
    • The community's growing irreligiousness worried the local clergy.
    • His irreligiousness was a source of tension in his deeply faithful family.
    • She wrote a book exploring the rise of irreligiousness in modern society.