The covenantal complexion of parables

Reading Keller's treatment of Luke 10:25-37 (Good Samaritan) and Luke 15:11-32 (Prodigal Son) I can't help feeling that he doffs the cap to biblical context and ends up worshipping at the altar of contextualization and that in his great concern to reach out he underplays the reaching in. Christ was concerned about faith and life within the covenant as exemplified by the father's love for his wayward son on the one hand, and his resentful son on the other and also by the fact that a stranger to the covenant actually demonstrated covenant love to one of the covenant people in a way that prominent members of the covenant community did not. The 'go and do likewise' is not a mandate for general social action but an urging of covenant love on one's fellow covenant members. Nor is it a command that is impossible for anyone but Christ to keep. To say that it is makes nonsense of the parable and of the command to do likewise . I understand that this cuts little ice with church growth & urban mission enthusiasts but seem to recall that it is the love Christians have for one another that makes the impression on those outside.

I have been dipping into The Urban Face of Mission (Ortiz & Baker eds, P&R) in order to revisit the spring from which Tim Keller drinks and to remind myself that this is the same current that feeds the missiological impulse. It is, of course, a sphere in which 'context is king' but not necessarily biblical context. Uppermost in this missiological hermeneutic is 'contextualization' - the various processes by which a local church integrates the Gospel message (the text) with its local culture (the context).' (Luzbetak cited by Barker, 75).

In the great hermeneutical spiral we are supposed to exegete the text and be exegeted by it. In the process of contextualization, who  or what 'exegetes' the context?  It is becoming increasingly challenging to imagine how a hermeneutic so influenced by its inter-face with cultural contexts can exegete those cultures. Sola scriptura has gone out of the window. In its place are social anthropology, demographics and others, each helping to create a hermeneutic not unlike the 'New Perspectives' with a standpoint and perspective distinctly extra-biblical and decidedly un-confessional. We live in free countries so each to his own; just don't called it 'reformed'.