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Jephthah (n.)

Bible (Judges 11): judge in Israel who promised God to sacrifice the first he met if he returned home victorious; this proved to be his daughter

3H6 V.i.91	[George to Warwick] To keep that oath were more impiety / Than Jephthah, when he sacrificed his daughter
Ham II.ii.402	[Hamlet to Polonius] O Jephthah, judge of Israel, what a treasure hadst thou!