Sunstone said:
How about Leviticus was told by God that eating shellfish is a sin, but eating shellfish is nutritious.
Or, Leviticus was told by God that wear fabric of two cloths is a sin, but fabric of two cloths often has superior qualities of wearability, comfort, washability, etc than fabric of one cloth.
Will those do for a discussion?
Not very
The law of Moses had been abolished long ago and these limitations are not applicable now - but there are still some points we can use.
Eating shellfish. It was a question of ritual purity, besides the Jews had enough food to feed themselves. As I have said, it is not applicable now, but let us imagine we are Jews and now it is 600 BC. Would I personally eat shellfish, knowing that this is nutritious?
No, and that is why: God created very many nutritious things (e.g., grain, grape, calves, cows... humans) but for some reason He decided to limit or prohibit consumption of some of them. The people of Israel should be clean, because it is chosen people to deliver the Savior once, and being member of this chosen nation I would better obey the Creator of the Universe, in confidence that He knows better.
Mixed fabrics. The reason for that was, again, purity and separation from the nations which done abominable things. Mixing fabrics could be a part of some pagan ritual, for example. Again, being a God-fearer at the time of the Mosaic covenant, I'd rather obey this limitation.
And the last point: an answer in the form of a question.
The reason tells me that God is ultimate reality. Disobeying Him can result in death - instant or delayed, but imminent; waging war against Him is utter insanity.
Would the reason drive me to insist on nutritiousness or washability as a really reliable criteria on how to act?