"Pelagians, Semi-Pelagians, and Arminians raise a serious objection to this doctrine of providence. They maintain that a previous concurrence, which is not merely general but predetermines man to specific actions, makes God the responsible author of sin. Reformed theologians are well aware of the difficulty that presents itself here, but do not feel free to circumvent it by denying God's absolute control over the free actions of His moral creatures, since this is clearly taught in Scripture, Gen. 45:5; 50:19,20; Ex. 10:1,20; II Sam. 16:10,11; Isa. 10:5-7; Acts 2:23; 4:27,28. They feel constrained to teach:
(a) that sinful acts are under divine control and occur according to God's pre-determination and purpose, but only by divine permission, so that He does not efficiently cause men to sin, Gen. 45:5; 50:20; Ex. 14:17; Isa. 66:4; Rom. 9:22; II Thess. 2:11; (b) that God often restrains the sinful works of the sinner, Gen. 3:6; Job 1:12; 2:6; Ps. 76:10; Isa. 10:15; Acts 7:51; and (c) that God in behalf of His own purpose overrules evil for good, Gen. 50:20; Ps. 76:10; Acts 3:13.
This does not mean, however, that they [Reformed theologians--CD] all agree in answering the question, whether there is a direct, immediate and physical energizing of the active power of the creature, disposing and pre-determining it efficaciously to the specific act, and also enabling it to do that act. Dabney, for instance, while admitting such a physical concurrence in the lower creation, denies it with respect to free agents. The great majority, however, maintain it also in the case of free moral beings. Even Dabney agrees that God's control over all of the acts of His creatures is certain, sovereign, and efficacious; and therefore must, along with the others, face the question as to the responsibility of God for sin. He gives his conclusion in the following words:
'This, then, is my picture of the providential evolution of God’s purpose as to sinful acts; so to arrange and group events and objects around free agents by His manifold wisdom and power, as to place each soul, at every step, in the presence of those circumstances, which, He knows, will be a sufficient objective inducement to it to do, of its own native, free activity, just the thing called for by God’s plan. Thus the act is man’s alone, though its occurrence is efficaciously secured by God. And the sin is man’s only. God’s concern in it is holy, first, because all His personal agency in arranging to secure its occurrence was holy; and second, His ends or purposes are holy. God does not will the sin of the act, for the sake of its sinfulness; but only wills the result to which the act is a means, and that result is always worthy of His holiness.' 1
The vast majority of Reformed theologians, however, maintain the concursus in question, and seek the solution of the difficulty by distinguishing between the materia and the forma of the sinful act, and by ascribing the latter exclusively to man. The divine concursus energizes man and determines him efficaciously to the specific act, but it is man who gives the act its formal quality, and who is therefore responsible for its sinful character. Neither one of these solutions can be said to give entire satisfaction, so that the problem of God's relation to sin remains a mystery" (Louis Berkhof, Systematic Theology, pp. 174-175).
1. Syst. and Polemic Theol., p. 288.