I think theological progress (and regress) happens broadly like this. There is a new and powerful insight into some theological locus, or into the whole scheme of Christian doctrine. 'New and powerful' does not always mean true and helpful, so there will be and should be a debate about whether this insight is in fact an improvement on what has gone before. Depending on how this debate goes, this new insight may become the new orthodoxy, generally accepted as the best way, or at least a good way, of expressing Christian doctrine in the here and now. Over time, though, this new orthodoxy becomes brittle. It is perhaps explained and explained until the kernel of the original insight is lost behind scholastic definitions, or it is defended and defended until the keep of the original insight is almost invisible behind the curtain walls of apologetics. At that point people start to question, start to look for new insight... And the cycle begins again.
I see this as a virtuous cycle, if - and only if - at the stage of looking for new insight the church looks to, and determines to be reformed by, the word of God in Holy Scripture. If it does so, and if individuals within the church who are asking questions are looking to Scripture for answers, there can really be nothing to fear. The old orthodoxies may have become clouded by time; they may simply have been valid and necessary expressions of the gospel in their context which no longer communicate as they used to. In that case, the central concerns of the old orthodoxies themselves demand that the schemes and ideas be revisited and questioned.
So, always learning. The church should not be afraid of doubters and questioners. They have the potential to help us to understand and express the gospel better than we would otherwise.
But there is a worry. Today we seem to have broken the cycle, or rather we have got stuck in one part of it. We are questioners and doubters. The old orthodoxies do not speak to us or to the world around us as they once did. We long for authenticity, something which does not just repeat the words our forefathers used, but speaks in our voice, addresses our concerns.
So far so good. But are we going back to Scripture for answers?
I think for many of us the questioning and doubting has come to have value in itself. We have become convinced that authenticity requires us to be always questioning, always holding opinions lightly, always doubting. To poke holes in the old orthodoxies has become commendable for its own sake, and those who do it best are applauded.
Always learning, but never able to arrive at a knowledge of the truth.
This is a problem of reaction. The old orthodoxies have become oppressive to us. For many people, their doubting and questioning is a response to a Christian upbringing which squashed questions, denied doubts, simply asserted the old truths in the old ways. In the name of authenticity, we cast them off. This could have been a glorious moment, if only we had gone back to the Word. If authenticity had been the first word in a conversation which had Jesus Christ as its final word, this could have been a reformation. But instead authenticity became the first and last word. Authenticity is certainly a human virtue, but to exalt a human virtue into the place of the word of God is idolatrous. No surprise that we are left applauding those who, by teaching anti-gospel ethics in the name of authenticity, have subjected themselves to the Scriptural malediction that it would have been better to be weighed down and thrown overboard.