Ross Douthat on the development of doctrine:
“The development of doctrine is supposed to deepen church teaching, not reverse or contradict it. This distinction allows for many gray areas, admittedly. But effacing Jesus’ own words on the not-exactly-minor topics of marriage and sexuality certainly looks more like a major reversal than an organic, doctrinally-deepening shift.”
This principle holds, albeit with some minor alterations, for confessional churches (at least those that are meaningfully confessional) in that there is a theological tradition–different from mere custom and rooted in Scripture–that our contemporary theologizing must be be faithful to.