SteelHead wrote:The Bible also teaches where there is no law given there is no sin. Rom 4:15 and 5:13. So is there an express commandment against polygamy?
Matthew 19:3-9
3 Some Pharisees approached him, and tested him, saying, “Is it lawful for a man to divorce his wife for any cause whatever?”
4 He said in reply, “Have you not read that from the beginning the Creator ‘made them male and female’
5 and said, ‘For this reason a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh’?
6 So they are no longer two, but one flesh. Therefore, what God has joined together, no human being must separate.”
7 They said to him, “Then why did Moses command that the man give the woman a bill of divorce and dismiss [her]?”
8 He said to them, “Because of the hardness of your hearts Moses allowed you to divorce your wives, but from the beginning it was not so.
9 I say to you, whoever divorces his wife (unless the marriage is unlawful) and marries another commits adultery.”
Mormons and Protestants interpret this as an injunction against divorce, alone. However, Catholics ask the question, "why is it that whoever divorces his wife and marries another commits adultery?" Does anyone under the sun view divorce, alone, as adultery? The "committing adultery" is in the "and marries another". Why would this be a case of committing adultery? The answer the Catholic Church gives is that Jesus indicates, very clearly here, that divorce does not separate what God has joined. The person is still married. Jesus then says, if a person who has divorced, marries another, they are committing adultery.
This is a clear indication, that a) marriage is between one man and one woman...the two become one, and b) marrying another while still married is committing adultery.
This is why, in the Catholic Church, if a divorced person wishes to remarry, they have to go through the process with the Church of showing that their previous marriages(s) were not "legal marriages", the legality/validity in question not secular, but under Canon Law. If a previous marriage is legally valid, the person is not allowed to remarry, as it would be a case of the Church sanctioning adultery. Of course, many Catholics do divorce and remarry (secular), but in cases where a previous marriage is still in effect (under Canon Law), they are considered to committing a mortal sin (adultery).
Hope that helps.