About 1,000 words in length, and written no later than the 8th century CE, the Hebrew Sefer Yetsirah (Book of Creation) is attributed by tradition to no lesser a figure than the patriarch Abraham. Its terse and esoteric nature has made it ripe for commentaries—by both rabbis and modern scholars—which have understood it in radically different ways. Tzvi Langermann describes the book and some of its interpretations:
The “book” itself contains very little prose; it consists mostly of catalogs of the components of the cosmos, in groups of two (pairs of opposites), three, and seven, and their sums—10, 12, 22, and 32. The cataloged components are those making up the physical universe, the human body, and time. The 22 letters of the Hebrew alphabet are very significant [to the author] as well, and are matched to the other components of the universe. . . .
Some claim that [the book] was originally meant to be a work of mystical magic, but this reading is clearly prejudiced by the kabbalistic appropriation of the text, a process which began in the 12th century, and, even more so, [by] a fierce turf defense by academic specialists in the Kabbalah. . . .
[H]owever, the first interpreters of Sefer Yetsirah read . . . it as a book of science. We possess extensive commentaries [in this vein], in Judeo-Arabic and in Hebrew, written by individuals throughout the Jewish Diaspora in the early medieval period. . . .
A mammoth sea change in the [book’s] interpretation was initiated by Isaac the Blind (late 12th-century Provence), one of the seminal figures in the spread of the Kabbalah. . . . Isaac was the first person to identify the ten s’firot, usually translated as “emanations,” mentioned at the beginning of Sefer Yetsirah with the s’firot of the Kabbalah. . . . At the same time, however, Isaac did not reject the philosophical-scientific reading established by earlier commentators. Instead, he built upon it; in his day, Kabbalah and philosophy were alternatives, not enemies, as they would later become.
Read more on Tablet: http://www.tabletmag.com/jewish-arts-and-culture/243868/sefer-yesira-text-commentary