Romans 9:18

And whom he will, he hardeneth. [3] That is, permits to be hardened by their own malice, as it is divers times said in Exodus, that Pharao hardened his heart. God, says St. Augustine, is said to harden men's hearts, not by causing their malice, but by not giving them the free gift of his grace, by which they become hardened by their own perverse will. (Witham) --- Not by being the cause, or author of his sin, but by withholding his grace, and so leaving him in his sin, in punishment of his past demerits. (Challoner)

[BIBLIOGRAPHY]

Et quem vult indurat. &c. St. Augustine, lib. de Gra. & Lib. Arb. chap. 23. Deus induravit cor Pharaonis, & ipse Pharao per Liberum Arbitrium. Quærimus meritum obdurationis & invenimus: merito namque peccati, universa massa damnata est: nec obdurat Deus impertiendo malitiam, sed non impertiendo misericordiam:....quærimus autem meritum misericordiæ, nec invenimus: quia nullum est, ne gratia evacuetur, si non gratis donetur, sed meritis redditur. Obduratio Dei est, nolle miserere, &c. Pharao, says St. John Chrysostom, was a vessel of anger, but his was from himself; Greek: kai par eautou.