What I take to be the 'consensus', in NT circles, is the notion that Judaism of the first century was not the ugly step sister of Christianity. This is developed in a number of ways, but essentially Sanders looked at the Second Temple literature of the first century, and determined that Second Temple Judaism was no more legalistic than the Christianity in which Paul proclaimed (which is to say it is not a religion based on the notion of legalism, not that there were no legalists within the religion). There have been corrections to Sanders thought since 1976 (one wonders when the word new will cease to signify?). The most important and often most overlooked is that there was no monolithic, normative, orthodox Judaism of the
If Paul was not deriding the Judaic people for being legalists, then what was Paul on about?