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Corban
Corban [EBD]
a Hebrew word adopted into the Greek of the New Testament and left untranslated. It occurs only once (Mark 7:11). It means a gift or offering consecrated to God. Anything over which this word was once pronounced was irrevocably dedicated to the temple. Land, however, so dedicated might be redeemed before the year of jubilee (Lev. 27:16-24). Our Lord condemns the Pharisees for their false doctrine, inasmuch as by their traditions they had destroyed the commandment which requires children to honour their father and mother, teaching them to find excuse from helping their parents by the device of pronouncing "Corban" over their goods, thus reserving them to their own selfish use.
Corban [NAVE]
CORBAN, an oblation, Mark 7:11.CORBAN [SMITH]
an offering to God of any sort, bloody or bloodless, but particularly in fulfillment of a vow. The law laid down rules for vows, (1) affirmative; (2) negative. (Leviticus 27:1; Numbers 30:1) ... Upon these rules the traditionists enlarged, and laid down that a man might interdict himself by vow, not only from using for himself, bur from giving to another or receiving from him, some particular object, whether of food or any other kind whatsoever. The thing thus interdicted was considered as corban . A person might thus exempt himself from any inconvenient obligation under plea of corban. It was practices of this sort that our Lord reprehended, (Matthew 15:5; Mark 7:11) as annulling the spirit of the law.CORBAN [ISBE]
CORBAN - kor'-ban (qorban; doron; translated "a gift," "a sacrificial offering," literally, "that which is brought near," namely, to the altar): An expression frequently used in the original text of the Old Testament; in the English Bible it occurs in Mk 7:11; compare also Mt 15:5. It is the most general term for a sacrifice of any kind. In the course of time it became associated with an objectionable practice. Anything dedicated to the temple by pronouncing the votive word "Corban" forthwith belonged to the temple, but only ideally; actually it might remain in the possession of him who made the vow. So a son might be justified in not supporting his old parents simply because he designated his property or a part of it as a gift to the temple, that is, as "Corban" There was no necessity of fulfilling his vow, yet he was actually prohibited from ever using his property for the support of his parents. This shows clearly why Christ singled out this queer regulation in order to demonstrate the sophistry of tradition and to bring out the fact of its possible and actual hostility to the Scripture and its spirit.William Baur
Also see definition of "Corban" in Word Study