The term "Cheap Grace" was first widely introduced in Dietrich Bonhoeffer's classic, The Cost of Discipleship. This is how he defined cheap grace:
Cheap grace means grace as a doctrine, a principle, a system. It means forgiveness of sins proclaimed as a general truth, the love of God taught as the Christian ‘conception’ of God. An intellectual assent to that idea is held to be of itself sufficient to secure remission of sins… In such a Church the world finds a cheap covering for its sins; no contrition is required, still less any real desire to be delivered from sin. Cheap grace therefore amounts to a denial of the living Word of God, in fact, a denial of the Incarnation of the Word of God.
Cheap grace means the justification of sin without the justification of the sinner. Grace alone does everything they say, and so everything can remain as it was before… Let the Christian live like the rest of the world, let him model himself on the world’s standards in every sphere of life, and not presumptuously aspire to live a different life under grace from his old life under sin….
That is what we mean by cheap grace, the grace which amounts to the justification of sin without the justification of the repentant sinner who departs from sin and from whom sin departs. Cheap grace is not the kind of forgiveness of sin which frees us from the toils of sin. Cheap grace is the grace we bestow on ourselves.
Cheap grace is the preaching of forgiveness without requiring repentance, baptism without church discipline, Communion without confession, absolution without personal confession. Cheap grace is grace without discipleship, grace without the cross, grace without Jesus Christ, living and incarnate.
Justin Buzzard, in his book, The Big Story, compared cheap grace to decaf coffee. It looks, smells, and might even taste the same, but once you take a sip, nothing happens. Most coffee drinkers I know what the jolt of caffeine when they get their first cup in the morning. Cheap grace may look like grace but it is not the same. Yeah, it may make us feel good about ourselves but in the end is not grace at all. Denny Burk wrote:
The “cheap grace” that Bonhoeffer warns about is actually no grace at all. Nevertheless, this notion of grace has become all too common in many evangelical churches today. Perhaps you have heard it before. It is the grace that promises to rescue us but not to renew us. It is the grace that offers to save us from hell but not from our sins. It is the grace that accepts all sinners into the church but offers no discipline for sin within the church. Any so-called “grace” that leaves a man a slave to his sin is really no grace at all. Why? Because grace isn’t merely deliverance from judgment. It is deliverance from what makes us worthy of judgment. The apostle Paul says it this way:
For the grace of God has appeared, bringing salvation for all people, training us to renounce ungodliness and worldly passions, and to live self-controlled, upright, and godly lives in the present age.” –Titus 2:11-12, NASB
The true grace of God teaches us “to renounce ungodliness and worldly passions, and to live self-controlled, upright, and godly lives in the present age.” Grace doesn’t merely forgive sin. It conquers it.