In Christianity, missional living is the adoption of the posture, thinking, behaviors, and practices of a missionary in order to engage others with the gospel message. The missional church movement, a church renewal movement predicated on the necessity of missional living by Christians, gained popularity at the end of the twentieth century due to advocates like Tim Keller and others in the Gospel and Our Culture Network. Advocates contrast missional living with the concept of a select group of "professional" missionaries, emphasizing that all Christians should be involved in the Great Commission of Jesus Christ.
The missional living concept is rooted in the Missio dei (Latin, "the sending of God"). In 1934, Karl Hartenstein, a German missiologist, coined the phrase in response to Karl Barth and his emphasis on actio Dei ("the action of God"). In their view, missional activities stemming from God. The Triune God is the primary acting agent in the world and within the church.