The ancient Israelite tradition made no distinction between “body” and “soul.” Instead, biblical sources referred to a person, living or dead, as a nefesh (Lev. 5:17; Num 6:6). In the Greco-Roman period, the rabbis gradually shifted from biblical monism toward a moderate dualistic position. This shift took place in the middle of the second century CE and became most pronounced in the Talmudic literature of the third and fourth centuries as rabbinic sages speculated about the pre-existence of the soul, on the one hand, and the afterlife of the soul, on the other hand. The rabbis, however, did not articulate systematic philosophical anthropology even though their views were informed by Platonic and Stoic notions. Instead, the rabbis were concerned about the cultivation of the moral personality through observance of law and the sanctification of all aspects of life. Systematic reflections about the human self emerged in the medieval period as a result of Jewish interaction with Islamic philosophy, theology, and mysticism. This paper discusses conceptions of the human self in rationalist philosophy and kabbalah, the two main forms of Jewish self-expression in medieval Spain, by comparing Moses Maimonides (d. 1204) and Sefer ha-Zohar, composed in the late 13th century. The paper explains how Jewish thinkers understood the nature of the human soul, the relationship between soul and body, the meaning of human perfection, and the nature of the afterlife. The paper argues that while Maimonides’ Aristotelian philosophy and Zoharic kabbalah differed in their approaches to human personhood, they also shared the belief that observance of Jewish law constitutes (albeit interpreted differently) the exclusive path toward individual salvation. In this regard, both rationalist philosophy and kabbalah offered polemical Jewish responses to both Islam and Christianity, even though Maimonides was deeply indebted to Islamic philosophy and the Zohar attests to Christian influences.