Rabbi Isaac ben Abraham was a little-known scholar from the heretical Jewish group, the Karaites, who lived during the late 16th century in Troki, a suburb of Vilna (Vilnius), which by turns was in Poland or Lithuania. In 1593, the last year of his life, he wrote an incisive, cogent polemic against Christianity, which over the centuries has had an impact in Christian and Jewish circles that far exceeds what might have been predicted based on its obscure...