From angels and the afterlife to suffering and Divine providence, The God Book addresses all things spiritual through classic works of Jewish philosophy. Works summarized include the Rambam's Moreh Nevuchim (Guide for the Perplexed), Ramchal's Derech Hashem (Way of God), ibn Pakuda's Chovos HaLevavos (Duties of the Heart) and Hilchos Deios from the Rambam's Mishneh Torah.