Why do we learn Torah?
Among other reasons - to know what Hashem is thinking. What are His moral standards. The rest of the world make up their opinions based on various factors - social, economic, genetic and others. But it is all a guessing game. A guy writes an opinion piece in the NY Times. His opinion. They get 8,243 letters from people - each with a unique way of viewing the world. Each person sure that they are right. But why am I more likely to have the "correct" opinion [many dispute that there even exists such a concept] than the other guy?
So Hashem gave us the Torah and laid things out for us. So lighting a match on a Saturday morning doesn't seem to bad but a person who does so [under certain circumstances] is publicly executed 馃槦馃槦 Making a certain type of oil mixed with various spices for one's own needs incurs Divine excision - 讻专转!! I wouldn't think that on my own. One may not lend out his money with interest. Why not? I can rent out my house - why can't I rent out my money??
The examples are legion. The Torah teaches us right and wrong often in contrast to what we would have thought on our own.
That is why the Torah is such a gift. Instead of guessing, we have Hashem Himself guiding us to be the best people we can be. 馃槉
Mussar Haskel: Don't impose your preconceived notions of right and wrong on the Torah but rather draw the principles of morality from the Torah.