Action and consequence in "sin"

Most of us don't seem to consider the difference between an action and the consequence in assessing "sin."  For example, consider conjugal sex: it is not only not morally wrong, but blessed, but there is a little tinge of guilty pleasure that seems to be attached to having sex itself as reflected in the veneration for Mary as being "ever virgin" even though she was righteously married  and apparently the mother of other children. I think education has reduced that tinge somewhat, but the point remains that we tend to conflate action and consequence.

I was talking to a member of our Conservative branch about the question of what God's concern is and I said that I did not believe that God made arbitrary laws or rules, but everything from God indicates that it is consequences, emmediate or eventual of the action itself that are the consideration.  He said that he believe that God sometimes just says something is wrong.  How do you perceive this?

 Under the New Covenant the emphasis is not on law in and of itself, but on how love is reflected, and that deals pretty much entirely with consequences.  There are a number of scriptures that speak of the letter of the law versus the spirit and the point is that the intent of the law under consideration is what should be paramount in our investigation and perhaps the most concise statement of the fact that love fulfils the law is Romans 13:10 "Love does no harm to a neighbor. Therefore love is the fulfillment of the law."  The consequence is the focus.

Is the concern about "homosexuality" displayed in the Bible ONLY about selfish/profligate actions?
Under that scenario I have to wonder what consequences of a same sex committed relationship are more harmful than in a hetero-sexual relationship.