Genazym s offering (this Sunday!) the first edition of the classic סֵפֶר אֱמוּנוֹת וְדֵעוֹת לְרַב סְעַדְיָה גָּאוֹן (Istanbul 1562)

This is the book that launched (and legitimized!) the rational (non-Kabbalistic) approach to Torah and Judaism. written to rescue the religious Jew "drowning in doubt" (in the author's words)