In their quest to overturn common Christian morals, the progressives have now turned proof-texting on its head. In response to what they call "clobber verses," they have painstakingly put together references to various outmoded dietary laws and other stuff and cite them endlessly to show how silly we are to stick at converting the sins they admire into virtues. I find their Biblical scholarship as disingenuous as I find the other side's to be lazy.
In fact, I think both evangelicals and progressives are guilty at times of inventing their own past, the real Judeo-Christian past. The progressives, who think basing authority on the past is illegitimate in the first place, I see making up facts as required to support their case. The sad truth is, evangelicals, who constantly appeal to the past (the Biblical record as well as Church history), often have a view of the past that I don't think stands very strict scrutiny, either.
Whatever else the Gospel is, it is a Story. The Gospel goes back to the earliest parts of the Old Testament and is carried forward past the end of the New Testament into the age of the Church. We are writing the latest chapter of the Story. But we don't get to make it whatever we want. Self-righteousness always wants to make a "Mary Sue" of the Gospel, with a consequent loss of power; this is, in essence, what the progressives want to make of it. The challenge is to accept all that has gone before and attempt to write your chapter in such a way that will be true to the characters and theme. That will require us all to confess our sins and repent of them and mortify our swollen Selves, before the Editor will pass our manuscript.