August 15, 2026

Knock Until It Opens

Costly grace is the gospel which must be sought again and again, the gift which must be asked for, the door at which a man must knock.

Bonhoeffer wrote these words in The Cost of Discipleship, first published in 1937, drawn from lectures he gave at the underground seminary in Finkenwalde. He was training pastors for the Confessing Church, the wing of German Christianity that refused to bow to Hitler's demand for a compromised, state-controlled faith. Against the cheap grace offered by a church eager to keep its members comfortable, he insisted that real grace is costly precisely because it cannot be grasped once and set aside. It must be returned to, asked for, knocked on like a door, a discipline of persistence rather than a single transaction.