" Grace interpreted as a principle, pecca fortiter as a principle, grace at a low cost, is in the last resort simply a new law, which brings neither help nor freedom. Grace as a living word, pecca fortiter as our comfort in tribulation and as a summons to discipleship, costly grace is the only pure grace, which really forgives sins and gives freedom to the sinner. "

― Dietrich Bonhoeffer , The Cost of Discipleship