God's self-humbling toward us in Jesus Christ is widely recognized to be the crux of Barth's theology. Rarely are the implications of that move traced all the way to the Christian life, however. In Karl Barth on Friendship with God: Prayer, Partnership, and Transformation, Cambria Kaltwasser draws the points of connection between them by excavating an inconspicuous yet far-reaching motif: friendship with God.

According to Barth, God is pleased to enter a relationship of reciprocity with human beings in prayer, a relationship Barth names friendship. Tracing this theme across the Church Dogmatics, Kaltwasser shows how the character of God's self-election to covenant partnership has inseverable ties to the character of our life in Christ. Kaltwasser examines both friendship's explicit content by way of Barth's account of prayer and its implicit basis in Barth's doctrine of election as the claim of God. In both dimensions, Barth's appeals to friendship paint a distinctive picture of the Christian life as mutual love and shared agency.

Kaltwasser argues that this distinctive picture is threatened by Barth's abstract account of sanctification, where our life with God resembles less a friendship than a relationship of paternalism. To safeguard the integrity of Barth's portrait of the humble Lord and the friendship it enables, we must disentangle these two strands of his theology, discard the paternalism, and retain the friendship.

Examining Barth's treatment of human agency through the lens of friendship, Kaltwasser intervenes in longstanding disputes concerning the adequacy of Barth's account of the Christian life and highlights its promise for theology today.