Alpha the bible DOES state its a sin.
Matthew chapter 19
And I say unto you, Whoever shall put away his wife except it be for fornication, and shall marry another. committeth adultery: and whoso marrith her which is put away doth commit adultery
Now the key word is Fornication which is not exacly the same as adultery.
Though I fail to see why logicly speaking he wouldnt be able to remarry .
I think its the whole christian thing of two flesh becomming one.
Corinthians 6:18-20 & 1 Corinthians 7:1-2
"Flee fornication. Every sin that a man doeth is without the body; but he that committeth fornication sinneth against his own body. What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's. Now concerning the things whereof ye wrote unto me: It is good for a man not to touch a woman. Nevertheless, to avoid fornication, let every man have his own wife, and let every woman have her own husband."
But I did find a christian sight that actually deals with the sublect.
http://www.bible.com/answers/adivorce.html[/url]