16. The question of the use of philosophy in theology was debated much amongst Christians, and difficulty was experienced over settling the limits of its use when it came to detailed consideration. The Mysteries of the Trinity, of the Incarnation and of the Holy Communion gave most occasion for dispute. The new Photinians, disputing the first two Mysteries, made use of certain philosophic maxims which Andreas Kessler, a theologian of the Augsburg Confession, summarized in the various treatises that he published on the parts of the Socinian philosophy. But as to their metaphysics, one might instruct oneself better therein by reading the [84] work of Christopher Stegmann the Socinian. It is not yet in print; but I saw it in my youth and it has been recently again in my hands. 17. Calovius and Scherzer, authors well versed in Scholastic philosophy, and sundry other able theologians answered the Socinians at great length, and often with success: for they would not content themselves with the general and somewhat cavalier answers that were commonly used against that sect. The drift of such answers was: that their maxims were good in philosophy and not in theology; that it was the fault of heterogeneousness called [Greek: metabasis eis allo genos] to apply those maxims to a matter transcending reason; and that philosophy should be treated as a servant and not a mistress in relation to theology, according to the title of the book by a Scot named Robert Baronius, _Philosophia Theologiae ancillans_. In fine, philosophy was a Hagar beside Sara and must be driven from the house with her Ishmael when she was refractory. There is something good in these answers: but one might abuse them, and set natural truths and truths of revelation at variance. Scholars therefore applied themselves to distinguishing between what is necessary and indispensable in natural or philosophic truths and that which is not so.