St. Augustine addresses all of this. He spent his life doing so. And he wasn't a Calvinist. Essentially, God foreknows man's free choices (Predestination) and sets up the circumstances in which they occur (Providence). God creates the playing field, man creates the results God foresaw. The Merciful and Loving Father gives sufficient grace to all, but the reprobate reject it and choose sin and death. They are not "elect" because God has not created a world in which they are saved, although He could have done so, but perhaps only at the expense of the salvation of others.
A Treatise on Grace and Free Will -http://www.newadvent.org/fathers/1510.htm
A Treatise on the Predestination of the Saints - http://www.newadvent.org/fathers/1512.htm
Can this idea (the bolded portion) be cited in Augustine?
I'm not familiar with this idea in any of Augustine's works, certainly not his later works wherein he renounced many of his former errors concerning grace and free will.
Citation?