So God can lust? I mean, you could try and categorise lust as being exclusively a sin rather than an emotion, but the Bible states more than once that God is capable of jealousy despite jealousy/envy being a deadly sin, so it seems just as reasonable to conclude that, working from this basis, God can feel "sinful" emotions, too, rather than just pure ones.
Which raises the question: if God is perfect but can feel lust and jealousy, then are these emotions inherently sinful no matter who feels them, or are they only sinful for mankind, and not God?
We need to remember that God is a being of far more complex emotions that we are. We also need to remember that the bible was written largely by mankind. I honestly don't think that God lusts because lust has more to do with primitive sexual desires and I don't honestly believe that God has those in the sense that humans do. We must also remember that we are also more developed and complex animals. Mammals specifically.
I also think the terms jealousy and envy are used as a way for Moses et all to describe the emotion that God feels. I personally believe that God's feelings are far too complex for the human mind to understand, and what we can best liken to his emotion is human jealousy and envy.
God is a perfect and pure being. He cannot sin. Neither would He enforce a double standard in His laws.