Here is a short extract from a forthcoming chapter:
G. K. Chesterton once wrote that “heresy always affects morality, if it is heretical enough.” It is true to say that any form of error, and not just heresy, will show itself in some form of deficiency or delinquency in the life of the church and the Christian. If we follow the logic of Paul in the pastoral epistles we should expect false theologies to produce ungodly behavior. But there is a subtle danger with Chesterton's observation. The danger is that we will form in our minds a narrow and set idea of what that immorality could look like. And, based on that assumption, we will then expect those who are theologically compromised to be immoral only in that particular way. Yet in the history of the church there have been those who clearly and definitely embraced and taught error who were known for their personal moral integrity. In fact men as notorious as Pelagius and Faustus Socinus were respected in just this way. You would expect the opposite to be true wouldn't you? But there is more to it than a simple, straightforward, personal moral failure.
In recent writing on orthopraxy there has been a stress on the outworking of orthodoxy in terms of changed Christian behavior along the lines of the fruit of the Spirit. Sometimes this has been married with an affirmation that this kind of orthopraxy is in fact what orthodoxy is really all about. What has been neglected, in my estimation, is the stress on orthopraxy at the very point where it connects to orthodoxy. This is the kind of orthopraxy that values guarding the good deposit, of being found trustworthy with the mysteries of God, of rightly handling the word of truth, of keeping the faith, of holding firm to the trustworthy word as taught. These things are also included in biblical orthopraxy. So much so that a failure here may have eternal consequences for preacher and listener alike. It is a failure that is exacerbated when those guilty of it continue to exhibit this kind of ungodliness. A refusal to be corrected, and to hold on to views that deviate from the gospel, is itself a form of immorality and ungodliness. If we do not hold firmly to the gospel then we will have a chronically misshaped orthopraxy at a vital point. And, it should be said, it is a failure that will only be corrected by repentance.