The same is true for breaking all of God's other commands.Committing adultery is not loving to a spouse,
God's law defines what it means to love regardless of whether or not you think that you need to do that. If there was a different law that someone was not following, such as if someone were not keeping the 7th day holy, then they would need to be informed that that is not loving to God.and we don't need a law to know that.