The Torah is God's guide for how to do His will, how to love Him, how to love others, how to do good works, how to have a righteous conduct, and how to avoid having a sinful conduct. It was never given for the purpose of attaining righteousness through obedience to it, nor have I ever stated that it was, but rather attaining righteousness through the one and only way, by grace through faith, is for the purpose of attaining obedience to the Torah (Romans 8:4). We are made new creations in Messiah for the purpose of doing good works (Ephesians 2:10) and it is OT Scriptures that equip us to do every good work (2 Timothy 3:16-17).
Titus 2:11-14 For the grace of God has appeared, bringing salvation for all people, 12 training us to renounce ungodliness and worldly passions, and to live self-controlled, upright, and godly lives in the present age, 13 waiting for our blessed hope, the appearing of the glory of our great God and Savior Jesus Christ, 14 who gave himself for us to redeem us from all lawlessness and to purify for himself a people for his own possession who are zealous for good works.
Everything that God's grace brings it what our salvation looks like. It is for the purpose of training us to live in obedience to God's law and to renounce lawlessness. Grace is the divine influence upon the heart, and its reflection in the life, so when God's will is reflected in our lives, we will according to His guide for how to do His will. If we have faith in God that He knows how to live better than we do, then we will seek to live according to His guide for how to have a righteous conduct, for the righteous shall live by faith (Habakkuk 2:4).
To unpack what it means to be saved by grace through faith:
Our salvation is from sin, so we are saved from the penalty of doing what God's law says is sin through faith in a redeemer and we are being saved from doing what God's law says is sin by the grace of God causing His will, which he made known in His law, to be reflected in our lives, through faith that it is better to live according to God's will rather than our own.
It is true that we have all sinned and fallen short of the glory of God, but it does not follow at all that therefore we should stop practicing a righteous conduct, and stop refraining from having a sinful conduct, or stop following Messiah's example. Rather, when we falter and sin, we should repent and turn from our ways back to following God's ways.
Deuteronomy 30:19 This day I call the heavens and the earth as witnesses against you that I have set before you life and death, blessings and curses. Now choose life, so that you and your children may live
Moses was upfront with the fact that he was setting death before Israel, but he was also setting life before them, so choose life, and not disobedience. It would have been ridiculous to for Moses to have said that the law brings death for disobedience so therefore they should disobey it.
2 Corinthians 2:7 Now if the ministry that brought death, which was engraved in letters on stone, came with glory, so that the Israelites could not look steadily at the face of Moses because of its glory, transitory though it was,
After speaking with God, Moses' face shone with glory (Exodus 34:29-30), but this glory eventually faded, so this was the glory that was transitory, not God's glory. If Paul had said that God's law was transitory, then he would have been sinning (Deuteronomy 4:2) and a false prophet who was not speaking for God (Deuteronomy 13:4-6), so that's a pretty clear indication that you should reconsider your interpretation. Paul said that our faith in Messiah does not abolish God's law, but rather our upholds it (Romans 3:31).
Heaven and earth have not passed away and not all has been accomplished, both of which refer to end times, so I take Jesus at his word that not the least part has disappeared from the law, including sacrificial laws. Paul took a vow in Acts 18:18 that involved offering sacrifices (Numbers 6) and he was going to pay the expenses of others who had taken that vow in order to show that he continued to live in obedience to the Torah (Acts 21:20-24), so sacrifices did not end with the death or resurrection of Jesus, but rather they continued up until the destruction of the temple in 70 AD, and only stopped because there is no longer a temple in which to do them. However, there are prophecies about a third temple being built when sacrifices will resume (Ezekiel 44-46). So there is no picking and choosing which laws to obey, though there is still discernment is understanding how they apply.
1 John 2:4-6 Whoever says “I know him” but does not keep his commandments is a liar, and the truth is not in him, 5 but whoever keeps his word, in him truly the love of God is perfected. By this we may know that we are in him: 6 whoever says he abides in him ought to walk in the same way in which he walked.
In these verses, obeying Jesus' commands is associated with walking in the same way he walked, and he walked in obedience to the Torah, so he didn't command anything other than obedience to the Torah, which he taught how to do both by word and by example, and which we are also told to follow (1 Peter 2:21-22). Jesus was not in disagreement with the Father or the Spirit about which commands we should obey, but rather he said his teachings were not his own, but that of the Father (John 7:16) and that he only came to do the Father's will (John 6:38). The Spirit also has the role of leading us in obedience to God's law (Ezekiel 36:26-27).
Jesus did not add any brand new commands or subtract any olds ones, otherwise he would have sinned (Deuteronomy 4:2). In regard to John 13:34, the command to love our neighbor was nothing new because it was commanded in the OT (Leviticus 19:18), but what was new about it was the quality of the example, where we are to love others as he loved us rather than love others as we love ourselves. The Greek word translated as "new" refers to something that is new with respect to quality, something that is refreshed or refurbished, and does not mean brand new with respect to time. Another verse good verse that shows this contrast is Matthew 7:19, where it talks about wine that is brand new being poured into wineskins that have been refurbished:
http://biblehub.com/text/matthew/9-17.htm
Jesus summarized the law as being about how to love God and how to love your neighbor, and he loved us through his obedience to the law, so if we are to love in the way that he commanded, then we are also to obey the law in following with his example.
