With respect to the divine concurrence in the actions of moral agencies (men, angels) a distinction must be made between good and evil acts. With regard to evil acts (sins) Scripture teaches a) that God in His perfect holiness is so unalterably opposed to every evil work that He absolutely forbids and condemns it (Decalog); b) that God frequently prevents evil acts from occurring, Gen. 20, 6; and c) that, whenever He permits them to happen, He so controls them that they must serve His wise and holy purposes, Gen. 50, 20; Rom. 8, 28. Nevertheless the question remains: "How does God cooperate in evil actions that actually do occur?" On the one hand, we cannot say that these acts are done without God, for this would deny His divine concurrence (atheism); on the other hand, however, we must not ascribe to God these acts in so far as they are evil (pantheism). In other words, the divine concurrence makes God neither the author of, nor an accomplice in, evil acts.
The difficulty is satisfactorily removed if we bear in mind the dividing-line which Scripture here suggests; for while it is true that God concurs in evil acts, He concurs in them only in so far as they are acts (quoad materiale), not in so far as they are evil (quoad formale). "God concurs in producing the 'effect,' but not the 'defect.'" The proof for the first (quoad materiale) is given in Acts 17, 25-28; for men live, move, and have their being in God, and receive life, breath, and all things from Him, not only when they do good, but also when they do evil. The second (quoad formale) is proved from Deut. 32, 4; Ps. 92, 15, etc.; for there it is stated that the "Lord is upright" and that "there is no unrighteousness in Him." God's work is perfect; for He is "a God of truth and without iniquity; just and right is He."
Of course, this does not explain the whole mystery in divine concurrence, but it shows us within what confines we must restrict our thoughts on this matter. Speculations that go beyond this either result in self-deception, or they deny the truths of Scripture (Acts 17, 28 : God's providence ; Deut. 32, 4 : His righteousness). The doctrine that man alone is responsible for his evil deeds though God concurs in them must be strenuously maintained on grounds of both Scripture and conscience. The pantheistic error that God must be held accountable for human transgression is repudiated not only by Scripture, but also by man's own conscience (Rom. 2, 15: "their thoughts accusing").
Holy Scripture describes God's concurrence in evil actions also as permission (permissive providence). We therefore speak Scripturally when we say: "God permits evil, or suffers it to occur," Ps. 81, 12; Acts 14, 16; Rom. 1, 28, etc. As Hollaz rightly points out, such permission is a) not kind indulgence, as though it did not offend God when men commit sin; b) nor a mitigation of the Law, as though God granted men license to sin under certain circumstances; c) nor a weakness in God or a defect of knowledge or power on His part, as though He were ignorant of it or could not check it; d) nor indifference to sin, as though God were an unconcerned witness of it; but e) a negative act, inasmuch as God docs not place insuperable difficulties in the way of the sinner, but allows him to rush into iniquity, Matt. 26, 23. "God indeed permits, but does not will that which He permits." (Quenstedt.) Frequently also God, in His most righteous judgment (iustitia vindicativa), punishes sin with sin, Rom. 1, 24--28. But even in these cases He neither wills the original evil act, nor has He pleasure in the superadded sin. God is never the cause or abetter of sin, Ps. 5, 4-6; Rom. 1, 18f.
With respect to God's concurrence in good acts we must distinguish between acts that are done a) in His Kingdom of Power (regnum potentiae) and b) in His Kingdom of Grace (regnum gratiae). The first are civilly good works (iustitia civilis) and the second spiritually good works (iustitia spiritualis). The iustitia civilis God works in the unregenerate by His almighty government of all things (regnum potentiae) and rewards it with earthly and temporal blessings, Ex. 1, 20. 21. The iustitia spiritualis God works in the regenerate by the gracious operation of the Holy Ghost, who bestows not only the ability to do good (potentia agendi), but also works the good act itself (ipsum agendi actum), as Scripture clearly testifies, Phil. 2, 13; 2 Cor. 3, 5; Phil. 1, 29.