by Jacques Maritain
The divine plan is not a scenario prepared in advance, in which free subjects would play parts and act as performers. We must purge our thought of any idea of a play written in advance, at a time prior to time — a play in which time unfolds, and the characters of time read, the parts. On the contrary, everything is improvised, under the eternal and immutable direction of the almighty Stage Manager. The divine plan is the ordination of the infinite multiplicity of things, and of their becoming, by the absolutely simple gaze of the creative knowledge and the will of God. It is eternal and immutable, but it could have been otherwise (since it could not have been had there not been things). Once fixed from all eternity, once assumed as fixed in such and such a way from all eternity, it is immutable. And it is by virtue of the eternal presence of time in eternity (even before time was), by virtue of the embrace, by the eternal instant, of history in the making (perpetually fresh in its newness and indeed — as regards free acts — in its unforeseeability) that the divine plan is immutably fixed in heaven from all eternity, directing history towards the ends willed by God and disposing towards those ends all the actors in the drama and all the good God causes in them, while taking advantage, on behalf of those ends, of the evil itself of which they are the nihilating first cause and which God permits without having caused it.
By reason of this free nihilating, the creature has a portion of first initiative in the drama. Unless the free existent has received at one stroke an unshatterable impetus to good, it depends solely upon him whether he will or will not take the initiative of nihilating or of non-consideration of the rule, under the motions and activations which bear him towards good. Will he or will he not nihilate under the hand of the potter? As concerns his good or evil act, and the repercussions it may have upon what follows in the drama, it is at that instant in time, known from all eternity, that the immutable plan is simultaneously established from all eternity. Let us suppose that the free creature has not, in that instant, the initiative of the thing that is nothing. The initiative of nihilating not being seen from all eternity) in the free existent by the ‘science of vision,’ from all eternity, the primordial will of God (which willed the good act of this creature in the direction of the particular end towards which it ordained him) is confirmed by the definitive or circumstanced will. Thus from all eternity the accomplishment of this good act by this creature is immutably fixed in the eternal plan.
Excerpted from Existence and the Existent, by Jacques Maritain