Morus rejects the distinction: man's inability is physical, better called voluntary and malign
Some of the Reformed, however, seem to reject this distinction, Alexander Morus among others. He judges that man's inability for good is physical and should be called so, since it is born in us and passes into us together with our nature.
Calling it moral is careless, in his view, because in ordinary speech 'morally impossible' means not what simply cannot be done but only what is extremely hard and happens scarcely, with difficulty and seldom.
On this question he would rather divide man's inability into two kinds. One is involuntary, brought in from outside, or arising from weakness; the other is inward and voluntary and arises from malice, not weakness. To the second kind he assigns the inability ascribed to man regarding saving good. De Victoria Gratiae, disputation 6, thesis 13.
Latin
XXXVI. Sunt quidem inter Reformatos qui distinctionem istam improbare videntur, ut inter alios Alexander Morus. Nam impotentiam hominis ad bonum existimat Physicam esse & dici debere, quoniam nobis innata est, & in nos cum ipsa natura propagatur: eandem vero incaute moralem appellari, quia in usu communi illud Moraliter impossibile dicimus, non quod simpliciter fieri non potest, sed quod solum difficillimum est atque vix, aegre, & raro fit. Itaque mavult, quod ad hanc quaestionem attinet, impotentiam hominis distingui in eam quae est involuntaria, & extrinsecus accersita, aut profecta ab infirmitate: & in eam quae interna & voluntaria est, & proficiscitur a malignitate, non ab infirmitate. Ad quod posterius genus revocat impotentiam quae homini tribuitur respectu boni salutaris. De Victoria Gratiae Disput. 6. Thesi 13.