I do think God would try to convey what love consists of to men. In fact, I think He is still doing that today. But I think His greatest method of conveyance was the Bible in its entirety.
Im not discounting the importance of the 10 commandments, but I also do not find what they say significantly more compelling that anything said by Jesus…on the one hand you have God writing down thing, on the other you have God speaking. In both cases, these things were conveyed to us through the Bible.
Likewise, I do not know that the lessons of the 10 commandments is significantly more important than the lessons of loyalty given to us in the Book of Ruth. The 10 commandments are easy to remember, but is God saying it is more importantt to not kill than to be loyal? I dont know, the Bible has 1 line about not killing, and several books about loyalty. So I think there are some questions there.