From the NY Times:

“Born in Boston on March 26, 1931, Leonard Simon Nimoy was the second son of Max and Dora Nimoy, Ukrainian immigrants and Orthodox Jews…Mr. Nimoy published “Shekhina,” a book devoted to photography with a Jewish theme, that of the feminine aspect of God. His black-and-white photographs of nude and seminude women struck some Orthodox Jewish leaders as heretical, but Mr. Nimoy asserted that his work was consistent with the teachings of the kabbalah.

His religious upbringing also influenced the characterization of Spock. The character’s split-fingered salute, he often explained, had been his idea: He based it on the kohanic blessing, a manual approximation of the Hebrew letter shin, which is the first letter in Shaddai, one of the Hebrew names for God…”…read the rest, here.