Thanks MarysLurker. However, Calvin, Luther, etc. would likewise agree completely with your statement that God does not work evil in the heart of the non-elect. You need to read the R.C. Sproul article I linked to above. For all parties, Calvin, Luther, St. Augustine, etc.—the predestination or reprobation of the non-elect is accomplished through God giving them over (justly) to the condemnation and power of original sin and the actual sin that flows from it. God is not working sin in their heart, rather He is justly withdrawing His softening grace from them and thereby hardening their hearts.
In contrast, in the case of those elected to glory God is working inwardly to overcome the sinful motions of the heart and to produce the fruits of righteousness, etc.