The pattern of ten as a full set recurs widely. In the Kabbalah the divine unfolds through ten sefirot, the emanations diagrammed as the Tree of Life, a scheme set out in the Sefer Yetzirah and elaborated in the Zohar. Hindu tradition gives the dashavatara, the ten principal descents of Vishnu, from the fish to the still-awaited Kalki. Sikhism recognises ten human Gurus before the Guru Granth Sahib assumed the office. The Ten Commandments anchor Jewish and Christian ethics, and Jesus tells parables of ten virgins and ten coins. Buddhism counts ten fetters and, in the Zen tradition, ten ox-herding pictures charting the path to awakening. The recurrence is not coincidence so much as convenience: in a base-ten culture, ten is the natural size for a list meant to feel exhaustive.
Sefer Yetzirah does not simply list ten sefirot in passing, it insists on the figure: "ten and not nine, ten and not eleven" is the text's own phrase, the earliest enumeration of the sefirot in Jewish mysticism and the point from which the later Kabbalistic Tree of Life is built. Walter Burkert's study of the Pythagorean tradition draws the opposite lesson from the same territory, that the arithmological reading of the first numbers, ten as completion among them, reaches modern readers through Neopythagorean writers centuries after Plato and cannot be traced to Pythagoras himself, whose own activity was religious rather than mathematical.