Occasion. The thirty-fifth disputation of the fourth Leiden cycle, defended 1 July 1606 under Arminius by Ioannes Casimirus Iunius. Its preface places it after the treatment of the Church, both the whole Church called catholic and the part called visible and militant. In the Syntagma it is followed by Trelcatius's Disputation XXXVI. It is a different text from Stanglin XLIX (Gerhartus Helmichius, 1605), which treats the same locus in an earlier cycle.
Authorship. By the convention of the Leiden faculty the theses are the presiding professor's; the student defended them. Stanglin argues the case for Arminius's authorship of the disputations at length, and it is his argument, not ours.
The doctrinal move. Arminius first fixes which Church's marks are sought, the militant (I), and defines a mark as an external, sensible accident (II), unfolding the definition term by term (III–VI). He then divides marks into probable signs (εἰκότα) and certain signs (τεκμήρια), and sets the first aside (VI–VII). The certain signs he derives from the Church's form, the relation of head and members: the word and its seals (VIII–X). He next extends word and seals across every age of the Church (XI–XVII), and finally uses the marks to rank churches by grade, purity and clarity, with the Roman Church as the running case (XVIII–XXI).
Where it is answered. No answer by Gomarus or in Wesley's writings is identified for this disputation. Its named opponents are the Pontificians (X) and the Roman Church (XVIII, XX, XXI).