ANSWER: Mark 7 is the only place in the King James Bible where Jesus comments about Corban. He offers these comments as a response to some self-righteous religious leaders who criticized his disciples for failing to wash, ceremonially, their hands before eating. He states, "For Moses said, 'Honor your father and your mother'; and, 'The one who speaks evil of father or mother, let him be put to death.' But you say, 'If a man shall say to his father or mother, "Whatever benefit you might receive from me is corban" (that is, set aside as a gift to God), he is not obligated to help his parents.'" (Mark 7:11 - 12, HBFV).
Jesus was condemning the general practice of the Pharisees of bypassing God's laws and substituting them with their own traditions through Corban. The case you cite is one of the many the Lord denounced. According to Strong's Concordance #G2878, the word is of Hebrew - Aramaic origin and means a votive offering or a gift consecrated to the funding of the temple. Thayer's Greek Definitions states that Corban is a gift offered to God through the temple's sacred treasury.
The Treasury of Scriptural Knowledge states that the practice of Corban was common among the Jews. The Pharisees would release, by their own authority, a child from supporting his parents. Amazingly, according to the TSK, these religious leaders would deem it sacrilege if such a person afterwards decided to go ahead and support those who gave birth to him!
Easton's Bible Dictionary states that a person could not reclaim anything designated as Corban. Jesus hated this practice of the Pharisees, as their traditions in this area nullified God's commandment that children should honor their parents. Their teaching gave people an excuse for not helping their father or mother and at the same time offered them the opportunity to use such designated good for their own selfish use.
God has instituted the fifth commandment for the explicit purpose of honoring one's parents (Exodus 20:12). Unfortunately, human beings have consistently tampered with his instructions and this is one case. One of the ways to honor parents is by giving them financial support when in need, especially when they are in old age. Children were obliged to adhere to the law whether they loved their parents or not. However, with the permission of the Pharisees, they could circumvent part of the law by dedicating money meant for the parents to the temple. This is one example of how the Eternal's laws were made "of no effect" and overridden by religious tradition.
Today the practice of Corban is alive and well but modified for the modern world. Some professing Christian organizations do inculcate a loyalty to the church organization above loyalty to parents. In many groups, dedication to a leader or denomination is leveraged as a means to increase the church coffers. Pressured members may take whatever money might benefit their parents and redirect it "for the good of the church." It is amazing what expediency or simply lack of righteousness can prompt people to do. It is this attitude of justifying disobedience to God, by adopting man-made traditions, that Jesus condemns.