In grafting we divide and open up the trunk, which will receive the graft. Now the fruit of this graft, selected by the gardener, is not the ordinary fruit of the tree to be grafted. In a similar fashion, the eternal Father whom the gospel mentions as the divine cultivator of the gospel, chose a wild plant from the earth (if we consider it in its origin and nature), which is humanity bearing the likeness of sinful flesh. God separated the nature from the person that would have been proper and connatural to it and that would have flowed out of its essence once it was actuated and existing. He substituted the heavenly graft, and the divine subsistence, the very person of his Son in the place of the human subsistence, which had been negated. Therefore this plant, divided in this way and wounded in what is most intimate, most appropriate and most connatural to its being, bears fruits that are different and do not belong to it, but rather to what was grafted onto it.

–Pierre de Berulle