William G. T. Shedd (1820-1894), American systematizer of Calvinist theology and professor at Union Seminary:
"Regeneration is to be defined as the origination of a new inclination by the Holy Spirit, not as the exertion of a new volition or making a new choice as a sinner. Keeping this distinction in mind, we say that in regeneration God inclines man to holiness and disinclines him to sin. This change of the disposition of the will is attributable solely to the Holy Spirit. The sinner discovers, on making the attempt, that he is unable to reverse his determination to self and the creature. He cannot start a contrary disposition of his will. He is unable to incline himself to God as the chief end of his existence. He can choose the antecedents or preparatives to inclining, but cannot incline. By a volition he can read his Bible. This is a preparative or antecedent to supreme love of God, but it is not supreme love and cannot produce it. By volitions he can listen to preaching and can refrain from vicious actions. These also are preparatives or antecedents to a holy inclination of the will, but are not this inclination itself and cannot produce it. It is a fact of consciousness that while the sinner can put forth single volitions or particular choices that are favorable to a new voluntary disposition because they evince the need of it, he cannot begin the new disposition itself. He cannot incline himself by any volition whatsoever.
"By the operation of the Holy Spirit in regeneration, the man is enabled to incline to holiness instead of sin. In the scriptural phraseology, he is 'made willing' (Ps. 110:3). God 'works in him to will' (Phil. 2:13). . . . By renewing the sinful and self-enslaved will, the Holy Spirit empowers it to self-determine or incline to God as the chief good and the supreme end. This new self-determination expels and takes the place of the old sinful self-determination. From this new self-determination or inclination or disposition or principle, holy volitions or choices proceed, and from the holy choices, holy actions."
--Dogmatic Theology, 3rd ed., ed. Alan W. Gomes (Phillipsburg, NJ: Presbyterian & Reformed, 2003), 765-766.