This essay seeks to analyze and compare several prominent early modern Catholic biblical commentaries on the question of grace, free will and predestination and the role in which the Church fathers had in shaping their approach. By comparing the commentaries of Franciscus Toletus, Cornelius Jansen (of Ghent), Thomas Stapleton, Gulielmus Estius, and Cornelius a Lapide on the fall of Judas in John 17:12, I hope to shed light on a neglected area in the history of exegesis. The paper will be structured as follows: first, I will provide a brief introduction and an explanation for including these five particular figures in the essay; second, I will discuss the three key patristic sources for the scholars of this era, viz. Cyril of Alexandria, Basil of Caesarea, and Augustine; and third, the paper will introduce the figures and analyze select passages of their commentaries that discuss the fall of Judas in John 17:12, while also paying attention to the role Augustine (and other auctoritates) play in the argumentation. Finally, some general conclusions will be drawn about grace, free will, and predestination among Catholic biblical commentaries in the early modern period and also the influence of Augustine on Catholic exegetes on this topic.