The evolution of church doctrine about homosexuality is itself a continuation of "the apostles' teaching and fellowship"

Over at TitusOneNine, my friend Philip Snyder of Dallas writes: 

Could, for example, General Convention vote that Baptism was to be in the name of Jesus only? How about GC voting to say that Jesus is of like substance with the Father or that the Trinity is not a true statement of the nature of God, but that God is truly one person with three (or more!) masks or avatars or functions?   

... In our baptism, the first promise that we make is to continue in the Apostles’ teaching and fellowship.  Where is the blessing of same sex unions within that teaching?  If it is not there, then why are you doing it?  If you think it should be there, why do you risk the apostles’ fellowship to impliment it before the rest of the church agrees?

I was pleased that Phil mentioned the two examples in his first above-quoted paragraph.

"The apostles' teaching and fellowship" included a willingness to let doctrines and practices evolve

Taking Phil's second example first: I thought it was generally accepted that church doctrine about the precise nature of the Trinity evolved over time, and was indeed eventually settled by being voted on in council. 

(At times back then the voting franchise seems to have been restricted to imperially-approved bishops — and the emperor himself — but that doesn’t mean we have to abide by the same restriction.) 

But the first example Phil gives, concerning baptism in the name of Jesus only, is even more interesting. As I’ve said before, if we’re to believe the reports in the Book of Acts, we must conclude that baptizing in the name of Jesus only is precisely what Peter et al. did, that is when they baptized in the name of anyone at all. This suggests unmistakably that one or both of the following is true:

Possibility A: Acts simply got it wrong in reporting that Peter et al. baptized in the name of Jesus only. In this case, we naturally wonder:

• what else in Acts and its prequel Luke might be wrong — no matter how carefully Luke investigated (see Luke 1), his sources might have misremembered or even “spun” their accounts;

• where the other scriptural authors might have erred in their writing (and there are plenty of candidates);

• what all this means for the scripturalist worldview.

Possibility B: Baptism in the name of the Trinity reflects an evolution in the church's thinking. Perhaps Acts didn't get it wrong, and the earliest church did indeed baptize in the name of Jesus only. This suggests that baptism in the name of the Trinity was a later innovation in the church’s practice, reflecting an evolution in theological thinking. We find indirect support for this view in the earliest-written gospel, that of Mark, in which the Great Commission does not contain the same trinitarian baptismal formula as the later Matthean version. 

It’s not evident that an evolution of baptismal practice either (i) originated with, or (ii) was approved by, the surviving apostles. If that had been the case, we might expect to read an account of the approval process itself somewhere, comparable to what we read of the circumcision controversy in Acts 15.

And speaking of the circumcision controversy: It was authoritatively resolved, not by Peter or any of the Twelve, but by James the brother of Jesus, who evidently was a latecomer to the church and does not have an obvious claim to authority via any dominical commission. 

Implication 1: Today's church is doing just what the early church did

Possibility B above — together with with the resolution of the circumcision controversy by James and not by any of the Twelve — strongly implies that in the early church, the apostles’ theological thinking and practices were not treated as immutable authority, but instead as the foundation for a continuing process of theological evolution.

If Possibility B is correct, and I think it is, then by engaging in The Current Disputes about homosexuality and the authority of Scripture, we are indeed continuing in the apostles’ teaching and fellowship; that is, we are working together to study and resolve claims of new insight as they arise, just as they did. And also just as in the early church, our resolution of claims of new insight might well involve departing from the specifics of what the earliest apostles thought and did.  Cf. 1 Thess. 5.19-21:  “Do not put out the Spirit’s fire; do not treat prophecies [that is, claims of new insight] with contempt. Test everything. Hold on to the good.”

Implication 2: The early church "adjusted" their writings to fit their evolving beliefs and practices

Another implication of Possibility B is that the early church felt free to put words in Jesus’ mouth, viz., in the Matthean version of the Great Commission, to match the evolution of thinking and practice.

That of course raises the question: What else in the NT might have been “adjusted” by later editors to fit the then-current thinking and practice?

Here's one example, about which I've written before:

There is some evidence that Luke's gospel may have been edited to emphasize Jesus's divinity. In Luke's account of Jesus's baptism, a voice from heaven makes a statement (Lk. 3:22). In most English translations, the statement is rendered, "You are my Son, the Beloved; with you I am well pleased." 

But scholars have noted that earlier manuscripts consistently provide instead a quotation from Psalm 2:7: "and a voice came from heaven, which said, 'you are my son; today I have begotten you.'" See, e.g., footnote 8 of Luke 3 in the New Living Translation: "Some manuscripts read and today I have become your Father." 

The earlier version has decidedly different implications for the nature of Jesus. It suggests that Luke and his sources may have regarded Jesus as an ordinary mortal until his baptism, at which time he was "adopted" by God as his son. It's possible that, in order to refute this so-called adoptionist heresy, the original Lucan text may have been altered.