I plucked this quote from Matt’s blog over at Into the Expectation. Apropos of the 9th day of Christmas, Polkinghorne’s take on participation offers a penetrating gloss on the deficiency of extrinsique grace à la de Lubac.

Human redemption comes through divine involvement, and not by an act of divine magic. The incarnation is the narrow point in which the large claim of universal salvific validity stemming from a particular life and death must balance. The human condition is such that it cannot be dealt with simply be an authorized representative (the Hebrew idea of shaliach), however inspired, but it requires actual divine participation. It is therefore essential, if Jesus is Savior, that God is fully present in him throughout. In Athanasius’ words, ‘He became man that we might become divine,’ so that we might share in the life of God and consequently that the life of God might be in him. Yet the Redeemer is not a gnostic Christ imparting the secrets of divine wisdom, who could indeed be a heavenly figure in human disguise. The mystery of our redemption is something altogether deeper than that. It proceeds, not from the outside by illumination, but from the inside by participation. We need transformation, not information.

John Polkinghorne, The Faith of a Physicists, 135.