George,
I was intending to move on but your question deserves a response.
When Christ began His earthly ministry, He proclaims (Mark 1:15), “The time is fulfilled, and the kingdom of heaven is at hand; repent and believe in the gospel.” Not a gospel. Not “take your pick among the various gospel options My adversary is dangling about you.” No, Jesus uses the definite article because He knows there is the one, true gospel that saves, among a variety of counterfeits.
The Apostle Paul knew there was one true gospel, and was so convinced of this that he became apoplectic when his spiritual children in Asia Minor strayed in their absolute adherence to it (Gal. 3:1). He was so irate at those who would alter that one, true gospel by adding a little human contribution to what saves the sinner that he damned such teachers to hell (Gal. 1:6-8). That is the attitude and language of someone who is certain there is one gospel to believe among an onslaught of evil options.
You ask why should Biologos choose one particular gospel? Here’s the best reason: because all those who believe any gospel other than the one true gospel are going to be subject to the wrath of Christ Himself when He returns with His mighty angels (2 Thess. 1:8), “in flaming fire, inflicting vengeance on those who do not know God and on those who do not obey the gospel of our Lord Jesus.” Again, there’s that definite article. It seems Jesus will be pretty worked up against those who miss what that one gospel is.
This last example shows why it is actually blasphemous to imply there are multiple competing gospels in Scripture of equal weight and imperceptible if any substantive differences. Why? Because the Bible says (Ps. 19:9), “the judgments of the LORD are true and righteous altogether.” How could that possibly be true if His gospel is veiled in any way? After all, He has promised to destroy those who do not believe and obey the true gospel when He returns. How righteous and just is the Judge who promises this retribution for failing to believe this particular gospel, and then makes it hard to know exactly what that gospel is? To hold that there are many optional forms of the gospel which might be chosen and embraced, all acceptable before God, is to call God a liar (for using the definite article when He writes about the gospel) and unjust (for throwing those who don’t know and believe it into hell).
The one true gospel is “the power of God for the salvation of all who believe, first for the Jew, then for the Greek.” It says the problem with the world is sin; that the answer to sin is the Savior; that the response to the Savior is surrender; and that the reward for surrender is salvation. Every true believer from the time of Christ’s earthy ministry until today has believed and been saved by this one true gospel. This is not my particular view of Scripture. This is the view that God has made plainly manifest on the pages of His Word.
If Biologos is desiring, as you suggest, “to show how evolutionary ‘science’ is compatible with several different interpretations of the gospel,” its mission is not only its own but the enemy’s as well.
Colin