Is it ensure, insure, or assure?
from Old English Fariseos, Old French pharise (13c.), and directly from Late Latin Pharisæus, from Greek Pharisaios, from Aramaic perishayya, emphatic plural of perish "separated, separatist," corresponding to Hebrew parush, from parash "he separated." Ancient Jewish sect (2c. B.C.E.-1c. C.E.) distinguished by strict observance but regarded as pretentious and self-righteous, at least by Jesus (Matt. xxiii:27). Meaning "self-righteous person, formalist, hypocrite" is attested from 1580s.