Such religious meaning must not be confused with the word 'belligerent' used to describe extremist religious behaviours found in some who, based on their extreme religious beliefs or ideologies, take up weapons and become involved in warfare, or who commit acts of violence or terrorism in an attempt to advance their extremist religious agendas. Such extremist groups can be Christian,[9][10] Muslims,[11][12][13] Jewish,[14][15][16] or of any other religious affiliation.