Leonard Nimoy was born in Boston, Massachusetts. His parents were Yiddish-speaking Orthodox Jews who immigrated from Ukraine (former Soviet Union). Max Nimoy, Leonard's father, owned a barbershop and Dora Spinner, his mother, was a homemaker.
Playing Spock in both television and movie versions of Star Trek, Nimoy's character used the hand gesture used by kohanim (Jewish priests) for his Vulcan salute. Nimoy created the Vulcan sign from his childhood memories of the kohen blessing the congregation in synagogue.
Leonard Nimoy explains the Priestly Blessing while wearing a tallit (Jewish prayer shawl) and how he came to create the Vulcan salute (video below):