In the following passage Jerome Zanchi, the Italian Reformer and friend of Peter Martyr and Zacharius Ursinus, appeals to the authority of Thomas Aquinas to demonstrate the orthodoxy of his own definition of original sin (something Peter Martyr also did). This definition assumes the correctness of the concept of original righteousness and the inherited guilt that accompanies the loss of that ontological status. Although Zanchi refers to Thomas as Scholasticus he places the current paragraph under the heading Confirmatio sententiae ex Patribus (confirmation from the opinions of the Fathers).
Thomas Aquinas eandem secutus est docrinam, & clarissime explicat, eum alibi tum in Quaestionibus disputatis, quaest. 4. de peccato originali, aritculo primo. Ubi concludit de actuali inobedientia Adae, eam convenire toti humano generi & singulis hominibus, quatenus omnes fuimus unum & sumus eum Adamo. Quod enim ille admisit, non illud eum admisisse ut privatum hominem, sed ut totius humani generis caput: quemadmodum etiam justitiam originalem non acceperat ut privatus homo, & sibi soli; sed ut pater omnium hominum, & nobis omnibus. Constat igitur nomine peccati originalis venire non solum justitiae originalis privationem naturaeque corruptionem, sed simul cum reatu & culpa inobedientiae Adami. Imo ideo cumprimis peccatum originale appelatur, quia omnes homines in Adamo tanquam in sua origine peccarunt. Sed interim non negatur altera ratio, nempe, quia quisque ex vitiosa origine peccatis concipitur nasciturque filius irae. Eadem doctrinam confirmant etiam alii seniores Shcolastici… (Zanchius, Commentarius in Apostolam Sancti Pauli Ad Ephesios, pp. 234, 235)
Thomas Aquinas followed the same doctrine, and explains it most clearly in other places and in the Disputed Questions, quest. 4 concerning original sin, article one. Where he concludes concerning the actual disobedience of Adam that it unites the whole human race and every human being, insofar as everyone was and is one with Adam. For although he committed this crime, he did not do it as a private individual but as the head of the whole human race: just as he did not receive original justice as a private individual or by himself; but as the father of all human beings, and for us all. It is agreed therefore that by the name “original sin” comes not only a privation of original justice and corruption of nature, but also the accusation and guilt of Adam’s disobedience. By all means therefore the first sin is called “original”, because all men sin in Adam as it were in their “origin.” But in the meantime another reason is not denied, namely, that whoever is conceived in sin from vicious origin is also born a son of wrath. Other older Scholastics confirm the same doctrine…
Many of those who consider themselves theologians in the Reformed tradition believe the Reformed position on Adam’s original state is antithetical to that of the Scholastics, positing a legal/ontological dichotomy between the language of “guilt” and that of “nature.” Here Zanchi shows no such dichotomy.