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Study Dictionary
Affinity
Affinity [EBD]
relationship by alliance (2 Chr. 18:1) or by marriage (1 Kings 3:1). Marriages are prohibited within certain degrees of affinity, enumerated Lev. 18:6-17. Consanguinity is relationship by blood.
AFFINITY [ISBE]
AFFINITY - a-fin'-i-ti (chathan "to join one-self"): This term is used three times in the Old Testament: (1) in 1 Ki 3:1, where we read that "Solomon made affinity with Pharaoh King of Egypt", (2) in 2 Ch 18:1, where it is stated that Jehoshaphat "joined affinity with Ahab," and (3). in Ezr 9:14, where it is asked "Shall we .... join in affinity with the peoples that do these abominations?" The Hebrew word thus rendered in the above three passages refers in each case to marriage alliances rather than to family or political relationships.See MARRIAGE; FAMILY.
W. W. Davies
Also see definition of "Affinity" in Word Study