What difference does the incarnation make?  For Athanasius, it means (among other things, of course) that grace is worked from within humanity rather than being offered extrinsically from without, as grace was given to Adam.

Redemption history is a movement from extrinsic to intrinsic grace, as the Father raises Adam’s children into communion by the Son and Spirit.

Or (borrowing the light/radiance analogy from Athanasius): Adam is illumined by external light; those of the new Adam are glorified by radiance within.