I have read a lot of the masterbation posts and there are people on both sides of the fence. A lot of them are opinions and not backed up with scripture, and although I respect all the opinions that were written and agree with some of them. I believe I have (in my mind atleast)the answer. In 1Corinthians chapter 7 vrs 5 says Defraud ye not one the other, except it be by consent for a season, that ye may give yourselves unto prayer, and may be together again, that Satan tempt you not because of your incontinency. To explain, A man and wife should not with hold themselves from each other"sexually" excep for a concented time, such as travel,menstrual periods or what ever and when that time is done then come together again. But during that time we are to be committed to prayer. Why? Because satan will tempt you with sexual thoughts and lust for self-gratification. I believe this applies to all men not just married men because paul went on to say that he wished that all were as he was, which was unmarried and totally commited to god, so if you are unmarried you should be busy doing what god has set for you to do and not centered on yourself. So yes, gratifying yourself or to please yourself is a sin.