It is my understanding that predestination is impossible with free will. The argument goes like this:
- Free will is only free when the will is without constraint;
- Predestination introduces constraint to the possible ends available;
- Therefore, free will does not exist if predestination is true.
This is why I went into a lengthy description of how we perceive time as linear, but God exists in all times past, present, and future simultaneously (this was reiterated by others) and therefore is able to know our choices without making them for us. In this respect, predestination
does not exist, and exception does not have to be made. I would reference my statement when I said that Mary’s conception without original sin, for God, did not necessarily precede her submission to him, but rather followed it. It is simply that within our linear understanding of the universe that conception precedes life. God instead would simply have to ask Mary “Do you submit to my will?” she answers “Yes” and then he allows her to be immaculately conceived.
To me, this makes God more awesome and more powerful than an all-knowing God confined to linear time and therefore is forced to make exceptions, precisely because by him doing so and predestining any to grace or glory fundamentally contradicts his promise and guarantee of free will.
Additionally, the fact that Saints and others “predestined for glory” (this just sounds like something a Baptist would say…

) represent for the Church an
attainable state of grace, showing that the call to be like unto Christ is actually doable, to me, also is proof positive that these people all retained their free will and were raised to their exalted state as a result. If they are truly predestined and we confine God to the linear time under which we exist and he is required to make exception and predestine people, it absolutely makes this exalted state unattainable except for those whose free will has been completely abrogated.
Predestination can be used to explain a situation such as the Immaculate Conception, but
only in understanding time the way I and others have explained it. If any other concept of time or any other method of predestination is presented as the basis of the argument, then predestination categorically must be false because it contradicts free will.