Regarding "desire" as a sexual urge or appetite. We have heard it said that, for example one can have homosexual feelings but not act on them and thus not enter into sin. That is, it is the acting on the thoughts, rather than the thoughts themselves that is the problem. Presumably this would also work for heterosexual thoughts as well. Yet, we are told in Matthew for example, that to even look upon a woman with lust is to commit adultery. Is this a question of intent i.e. the thought, matched with the intent (desire?), makes the sin or is it the thought itself regardless of intent? This seems to be an interesting question on a number of levels including but not limited to matters of linguistics, etymology and of course theology.
Next part, separate question. Regarding desire in relation to a longing or hoping. How much weight do you think should be given to those feeling that arise inside of a person to do some specific thing? For example, if one had a desire to write, a lifelong, unrealized ambition to do this thing, how serious should that individual take that feeling? Should they pursue it? You can insert any particular in the above example. I am reminded of the early try outs of "American Idol" here (the only part I'll watch but only by accident). Lifelong desire meets hard reality in many cases. Did no one tell them they couldn't sing? Or did someone tell them but they ignored it? Obviously this is part of the answer. Like Spiritual Gifts, such desire requires some community affirmation. But is there something more to say here?
Main Entry: 1de·sire
Pronunciation: \di-ˈzī(-ə)r, dē-\
Function: verb
Inflected Form(s): de·sired; de·sir·ing
Etymology: Middle English, from Anglo-Frenchdesirer, from Latin desiderare, from de- + sider-, sidus heavenly body
Date: 13th century
Main Entry: 2desire
Function: noun
Date: 14th century