Gysbert Voët (he Latinized his name as soon as he became a professional) was born at Heusden, a garrison town on the border with the Spanish Low Countries. During his theological studies at Leiden, he became involved with the Contra-Remonstrants, the ultra-orthodox wing of the Dutch Reformed Church, which adhered to a strong interpretation of predestination. After his studies he was minister in various places before being appointed (1634) professor of theology at Utrecht Illustrious School, which in 1636 was elevated to the rank of university. A learned and industrious man rather than an original scholar, he soon became one of the pillars of orthodox theology, publishing almost ten huge volumes of disputations and several books on practical theology, as well as preaching and fighting on many fronts: against relaxed variants of Protestantism (like Arminianism and Coccejanism), but also against Catholicism, libertinism, Socinianism, Cartesianism, and atheism. Moreover, he vociferously intervened against practical and social evils, like the theater, the desecration of the Sabbath, usury, and the worldly use of ecclesiastical goods. In his later career, he more and more emphasized the need of personal piety, consisting in a rigorous obedience to the will of God in combination with ascetic practices.

Like other orthodox theologians of his age, Voetius had a complex relation to philosophy. On one hand, he emphasized the absolute clarity of scripture, which moreover enjoyed an authority superior to any human truth; on the other hand, he felt that philosophy was indispensable in order to establish its true meaning. The solution of this paradox was to declare that “sound philosophy” is no more than a sophisticated form of common sense. Hence, he had a deep distrust in purely intellectual speculation. It is against this background that his reaction to Cartesianism must be interpreted. At Utrecht University, Cartesian philosophy was explicitly introduced in 1638 by the professor of theoretical medicine Henricus Regius, a friend of Descartes. Regius favored an aggressive approach, which in 1641 led to a confrontation with the theologians. They felt that several of Regius's ideas (on human beings, on the motion of the earth, on substantial forms) were a threat to systematic theology; they did not like the polemical way in which Regius presented his ideas; and they had no confidence in a philosophy of which no more than a few fragments were known and which as yet was not taught at other universities.