"Breaking the Rocking Horse" is a summation of some of the key points found in Marty's larger works defending the biblical doctrine of unconditional security (more popularly known as eternal security). The present book is a pictorial abridgement that demonstrates that the spiritual fruits produced by professing believers cannot be made the criterion by which to determine (or undermine) the genuineness of their profession. In short, the way one lives does not prove if one is saved. Proveitists is a coined term used within the book to describe the opposing theology of those who allege that the way professing believers live proves whether or not they are saved. The purpose of this book is to disprove proveitism. The notion that heaven is free initially but ultimately costly (in terms of necessary spiritual fruits) is shown to be an irrational back-and-forth rocking between irreconcilable propositions. God-enabled perseverance cannot be the requirement for a salvation that is not contingent upon human performance. Primary chapters within the book focus on the parable of the soils and the parable of the servants. The thesis of these chapters is that carnal believers (pictured by the second and third soils) are cast into the outer darkness (representing loss of rewards) rather than into hell. Assurance of salvation from hell, therefore, is not found in one's performance, but in Christ alone. The primary benefit of this book to the reader is to encourage a biblically accurate understanding of the gospel so that the reader may not be deceived unwittingly into seeking salvation from eternal damnation by an unbiblical means. Salvation from hell must be received as a free gift by grace apart from works. Logical inconsistency in this area can be highly detrimental. As an additional benefit, the reader is provided solid grounds for biblical assurance without being given grounds for sinful license.