The Greek word for “one and only” is monogenes, an adjective compounded of monos (“only”) and genes (“species, race, family, offspring, kind”). When used in the Bible, “one and only” almost always describes a parent-child relationship. Luke employs it to identify the widow’s son; “the only son of his mother” (Luke 1:12). The writer of Hebrews states “Abraham…was ready to sacrifice his only son, Isaac” (11:17 NLT). John enlists the phrase five times, in each case highlighting the unparalleled relationship between Jesus and God.