We Lutherans have gathered like eagles round the carcase of cheap grace, and there we have drunk of the poison which has killed the life of following Christ. It is true, of course, that we have paid the doctrine of pure grace divine honours unparalleled in Christendom, in fact we have exalted that doctrine to the position of God himself. Everywhere Luther's formula has been repeated, but its truth perverted into self-deception. So long as our Church holds the correct doctrine of justification, there is no doubt whatever that she is a justified Church! So they said, thinking that we must vindicate our Lutheran heritage by making this grace available on the cheapest and easiest terms. To be "Lutheran" must mean that we leave the following of Christ to legalists, Calvinists and enthusiasts - and all this for the sake of grace. We justified the world, and condemned as heretics those who tried to follow Christ. The result was that a nation became Christian and Lutheran, but at the cost of true discipleship. The price it was called upon to pay was all too cheap. Cheap grace had won the day.
I'm not convinced this exalting of the doctrine of free grace is the problem in reformed churches today, but this is a clear warning: we are not justified by the doctrine of justification. We are justified by Jesus. A misplaced focus will give birth to a host of errors and sins.