How do you persuade someone who already thinks they’re a Christian to become one? The largest mission field in Western Europe is not self-identifying atheists or Muslim immigrants; it is people who call themselves Christians but exhibit few, if any, signs of faith. A Pew Research Centre report stated that people who identify with Christianity, but rarely or never attend church services, make up the biggest segment of the region’s population. 46% of Western Europeans are non-practising Christians, 18% are regular church attendees, 24% are religiously unaffiliated, and 5% follow other faiths.