ESTIUS, GUILIELMUS (HESSEL VAN EST, WILLEM). - Exegete, theologian, and hagiographer, born at Gorkum (Holland) in 1542, died at Douai on 20 September 1613. After completing his early studies at Utrecht, he attended the University of Louvain, where he earned a doctorate in theology in 1550. Baius (v.), whose less orthodox ideas he adopted to some extent, though he remained deeply Catholic in sentiment, so much so that Benedict XIV described him as *doctor fundatissimus*. At the University of Douai, he first taught theology, then, from 1582 onward, Sacred Scripture; he served as its chancellor from 1595 until his death. He also served twice as rector of the Douai Seminary.
He wrote remarkable commentaries on St. Paul and the Catholic Epistles. Nearly all his works were published after his death and pertain to the Bible, theology, and hagiography.
Among his biblical writings, we note: *In omnes D. Pauli epistolas commentaria* (2 vols. fol., Douai 1614); *In quinque epistolas catholicas commentaria* (ibid. 1616). The notes from 1 John 5:7 to the end of the epistle, as well as those on the minor epistles of John, were added by the editor B. Peters (Petrus). This commentary, which constitutes his masterpiece, went through many editions (up to 1592 in Paris) and remains highly useful and sought after. He also wrote: *Amatoliones in praecipua ac difficiliora S. Scripturae loca* (Antwerp 1621). His biblical works were later published together in Venice in 1659 (*In S. Scripturam opera omnia*).
Among his theological works, we note: *Orationes theologicae* XIX (Douai 1614); *Commentaria in quatuor libros Sententiarum Petri Lombardi* (ibid. 1615, later Naples 1720). A hagiographical work, *Historia martyrum Corcu-meusium* (ibid. 1603), is the only one prepared during his lifetime.
