Messiah Yeshua, as the "Arm" (Isaiah 53:1) and the "Word of YHWH (John 1:1 and 14), is now the standard bearer. Moses is no longer the steward, thereby fulfilling the prophecy of Deuteronomy 18: "I will raise up for them a prophet like you from among their brothers; I will put my words in his mouth, and he will tell them everything I command him. If anyone does not listen to my words that 'THE' prophet speaks in my name, I myself will call him to account."
The Torah (YHWH's Divine Instructions in Righteousness) is administered (NOT replaced!) under a renewed covenant. A covenant whereby the Torah is "written on our hearts" (studied and memorized!) via the Spirit of God, and not on clay tablets alone. This fulfills the prophecy of Jeremiah 31: "This is the covenant I will make with the house of Israel after that time, declares the Lord. I will put my law in their minds and write it on their hearts. I will be their God, and they will be my people." Please note that YHWH made His "New Covenant" NOT with the Gentiles, or the Christians or the Muslims or anyone except for the Houses of Israel and Judah (Jeremiah 31:32).
The priesthood has changed. Instead of an Aaronic high priest, the high priest is one after the order of Melchizedek. That is, Yeshua. This fulfills the prophecy of Psalm 110, where King David writes: "ADONAI says to my Lord (God is speaking to someone King David calls Lord): 'ADONAI will extend your (the one King David says God is speaking to) mighty scepter from Zion; you will rule in the midst of your enemies. Your troops will be willing on your day of battle. Arrayed in holy majesty, from the womb of the dawn you will receive the dew of your youth. The Lord has sworn and will not change his mind: 'You are a priest forever, in the order of Melchizedek.'"
Under the renewed covenant, Messiah himself was our redeemer - our "substitute". He wasn't "sacrificed; he offered/martyred Himself, against which there is NO law! (We must remember that the "Passover Lambs" were NOT "sin offerings" nor were they sacrificed; they were offered as "substitutes"! If you'll recall, the "angel of death" passed over the believing Hebrews when the lamb's blood was on their door posts. So, though not a "sin" sacrifice, the lamb's blood was offered as a substitute, giving the Hebrew first-born males the chance to live.)
This is the whole connection: Yeshua was our redeemer, our "substitute" - and by believing and following YHWH's Torah to help us to lower our tendency to sin and do our best to NOT sin anymore, we have the chance for eternal life! This fulfills the foreshadowing of Psalm 40, relating to animal sacrifice because he CHOSE to martyr himself on our behalf: "Sacrifice and offering You did not desire; My ears You have opened. Burnt offering and sin offering You did not require. Then I said, 'Behold, I come; In the scroll of the book it is written of me. I delight to do Your will, O my God, And Your law is within my heart.'
IMPORTANT NOTE: The death of Yeshua in NO WAY negated our need to obey YHWH's Torah - His Divine Instructions are our ONLY blueprint for moral, holy living! According to Numbers 15:13-16, ALL who have accepted the God of Abraham, Isaac and Jacob are to be Torah observant.