I am trying to make the case for gospel-driven separation, so an obligation is laid on me, I believe, to demonstrate that the gospel is the center of the separation issue. Probably to no one’s surprise, I’d turn to the statement in 1 Corinthians 15:3 as evidence that my case is grounded on biblical priorities. As Paul begins to confront a very serious doctrinal issue, the resurrection, among the Corinthians, he lays the foundation for his argument by showing its connection to the gospel. He does this because the gospel is “of first importance” (v. 3).
It is important to understand the logic of his argument—you can’t deny the resurrection because denying it damages the gospel and the gospel is of first importance. The significance of the resurrection comes from its place as an essential element (i.e., belongs to the essence of) of the gospel. No resurrection means no gospel. By arguing in the way that he does, Paul shows us the priority of the gospel in our theological controversies. It doesn’t mean that other doctrinal controversies are insignificant, but that the ones that are of “first importance” are those that are tied to the gospel.
Because our day is plagued by an approach to the gospel which is reductionistic, I’d like to make clear that I don’t believe this fits this text or the rest of the NT witness about the gospel. Specifically, I think it is a serious misinterpretation to take vv. 3-4 as giving us a full expression of the gospel. Paul is providing a summary of the key historical events, assuming, because he is writing to the church at Corinth, that the full significance of these statements really constitutes the gospel.
Exegetically, I’ve always found it very odd that anybody could claim that vv. 3-4 present a statement of the whole gospel when the sentence also includes v. 5. So, if we are going to say that Paul intends vv. 3-4 to be a theological statement of the complete gospel, then we also need to include the matter of appearing to Cephas and the twelve in our gospel presentations.
Theologically, it is naïve to ignore the fact that every aspect of this summary is packed with understanding shared in common by the believers at Corinth and Paul, but that would not be apparent to those who have not heard the fuller explanation and exposition of the gospel. Take, for instance, the statement “that Christ died for our sins according to the Scriptures.” Think about what is comprehended in that simple statement: What does Christ mean? Who is this Christ? What kind of death did he die? What are sins? Why would He die for our sins? What are the Scriptures? The answers to these questions are all assumed by the statement because Paul was writing to people who have already accepted the gospel message (cf. v. 11 “so you believed”).
My contention would be that the gospel, as outlined in the NT, is fuller than most of the truncated gospel presentations of our day. That has implications for gospel preaching, but my main concern here is stating that calling for gospel-driven separation is not an attempt to minimize theological concerns. It is an effort to sharpen our focus on the point of concern—does this doctrinal deviation affect the gospel?
I would argue that this gospel-centeredness is why Jude uses the word “faith” in his famous statement about what was “once for all handed down to the saints” (Jude 3). Jude is not referring to our act of believing, but to the object of our believing—the message of the gospel. Colossians 1:23 provides a helpful parallel, “if indeed you continue in the faith firmly established and steadfast, and not moved away from the hope of the gospel that you have heard….” Here “the faith” and “the hope of the gospel” are two ways of saying the same thing.
This also accounts for the seriousness of theological error regarding the person and work of Christ. John makes it clear that departure from the apostolic doctrine of Christ means that one “does not have God” (2 John 9). Christological error is gospel error precisely because preaching the gospel is preaching Christ (cf. Phil 1:12-18; 1 Cor 2:2; 2 Cor 4:5). The problem at Galatia was a gospel problem, not just at theological debate about justification (Gal 1:6-9). Even his confrontation with Peter and Barnabas was based on the fact that “they were not straightforward on the truth of the gospel” (Gal 2:14). Whether the problem is one of creed or conduct, Paul sees the gospel at stake and moves to defend it.
God’s glory and man’s good is wrapped up in the gospel, and that makes us doubly obligated to guard the gospel. There is more to be said on this matter, but my point here has simply been to demonstrate that the gospel is another way of saying “the fundamentals of the faith” and, so, any doctrinal departure that tears at the gospel (i.e., denies a fundamental) is cause for separation from such false teaching and those who teach it.