"Love your neighbor as yourself" is actually a verse in the Hebrew Bible, the Torah, Leviticus 19:19. The verse is cited by the great Talmudic sage, Rabbi Akivah, as a "great rule of the Torah". Hillel, another great Talmudic sage, considers its negative form, "That which is hateful to you do not do unto your friend" to be an encapsulation of the entire Torah.