[1] Isaac's learning earned him the respect and deference of his fellow Karaites, and his knowledge of the Latin and Polish languages and of Christian dogmatics enabled him to engage in amicable conversations on religious subjects not only with Roman Catholic, Protestant, and Greek Orthodox clergymen, but also with Socinian and other sectarian elders.
The fruit of these personal contacts, and of Isaac Troki's concurrent extensive reading in the New Testament and the Christian theological and anti-Jewish literature, was his famous apology of Judaism entitled Hizzuk Emunah (Hebrew חזוק אמונה, "The Strengthening of Faith").
Among his radical Christian sources, though Isaac considered them adversaries still,[2] he made reference to the works of Belarusian "Psilanthropist" Symon Budny who was excommunicated from the Unitarian community for opposing prayer to Christ and denying the virgin birth.
The work at once won extensive popularity both because of its powerful defense of the Jewish faith and because of its calm and reasonable emphasis of what he saw as vulnerable points in Christian tradition and dogmatics.
But one manuscript copy, modified and amplified by a Rabbinite copyist, came into the hands of the Hebraist Johann Christoph Wagenseil, who published it, with a Latin translation, under the sensational title of Tela ignea Satanae (The Fiery Darts of Satan; Altorf, 1681).