Reflecting on the "law", it's interesting that the Mosaic Law describes and expounds upon the "moral law", but it does NOT create it or establish it. Rather, it *assumes* it. Even in the Garden, the serpent was evil because he lied, before any "law" about lying was given. We were made to know and obey these precepts, thus why even Gentiles are guilty before God, without the Mosaic Law or Ten Commandments being involved at all.
The Mosaic Law was *always* about gaining "wisdom and understanding" in order to walk with an "upright heart". Psalm 119 is a long love letter to God's laws, precepts, commands, rules, and testimonies. And in this psalm it emphasizes way more how God's laws give "wisdom and understanding", rather than personal moral goodness or commendable behavior. All of the demands of this Law was fulfilled and put aside in Christ, there's no need to "preserve" the "moral parts", it's not even a "law" for us anymore, only an opportunity to gain wisdom about God and ourselves. Let's call it the "Mosaic Wisdom" instead!
And indeed, Paul repeatedly and emphatically anchors his encouragement to live godly, righteous, and holy lives, in the encouragement to gain "wisdom and understanding" into the "will of God" which is contained in "God's commandments". And the principles of all of God's commands, are derived from the Great Commandments to "love God and one another".
So don't get legalistically hung up on the Ten Commandments. If we have faith in Jesus, and seek humble unity with God's people, we will fulfil the command to "seek first the Kingdom of God and his righteousness, and all the rest will be added to you." To paraphrase Augustine a bit, "Love God [and love one another], and do as you please."
