Through modern applications of the historical Christian "mark" of "holiness," Christian disciples can be assured that they are following God's will, with behaviour coinciding with God's revelation and the Church's mission. Insights gleaned from three thinkers lead to a model for the practical involvement of "holiness ethics" in the modern church, with each offering a key component to the model. Dietrich Bonhoeffer offers a way of understanding the world that provides a positive environment for church work. John Webster offers an inclusive understanding of God's holiness and how it flows to His human creatures. Emmanuel Levinas offers a manner of understanding how God's holiness-carrying people can be certain of where they need to be active in the world. Combined, the insights comprise a practical and encouraging model that is highly descriptive of the activity of the historical and modern evangelical church. Understanding their world, themselves, and their activity offers Christians confidence that they are doing the right activities toward the right people in the right place at the right time.