In fact we see Messiah telling them that they will be chased OUT of the synagogues for the testimony of Yeshua. He did not teach his followers they would need to learn the rest from the Torah read in the synagogues every Shabbat. He taught just the opposite.
Luke 21:12 ESV
But before all this they will lay their hands on you and persecute you, delivering you up to the synagogues and prisons, and you will be brought before kings and governors for my name's sake.
John 16:2 ESV
They will put you out of the synagogues. Indeed, the hour is coming when whoever kills you will think he is offering service to God.
So, what was the point in mentioning Moses being read in the synagogues every Shabbat?
Acts 15 verse 18 identifies it.
18
SAYS THE LORD, WHO MAKES THESE THINGS KNOWN FROM LONG AGO.
What things were made known long ago in the Torah that is now being revealed?
Isaiah 45
21 "Declare and set forth your case; Indeed, let them consult together. Who has announced
this from of old ? Who has long since declared
it? Is it not I, the LORD ? And there is no other God besides Me, A righteous God
and a Savior ; There is none except Me.
What was announced? What was declared? The Law?
God is the ONLY Savior. There is none except him. Yeshua is God our salvation.
What is it? Yeshua
Who has announced Yeshua from old? Who has long declared it? The LORD has! Yeshua et Adonai!
16 'AFTER THESE THINGS I will return, AND I WILL REBUILD THE TABERNACLE OF DAVID WHICH HAS FALLEN, AND I WILL REBUILD ITS RUINS, AND I WILL RESTORE IT, 17SO THAT THE REST OF MANKIND MAY SEEK THE LORD, AND ALL THE GENTILES WHO ARE CALLED BY MY NAME,'
What is restored through Yeshua? The tabernacle of Moses, or of David?
The reason the mention of hearing Moses teachings in the synagogue ever Shabbat is because through the reading of the Torah and the Prophets was the declaration about the coming Messiah, Yeshua.
John 1:45 ESV
Philip found Nathanael and said to him, "
We have found him of whom Moses in the Law and also the prophets wrote, Jesus of Nazareth, the son of Joseph."
The Torah leads to Messiah, Messiah does not lead to Moses, Moses leads to Messiah. So the Jews and converts, who were the ONLY ones in the synagogue, did hear every Shabbat about the salvation that is Yeshua HaMoshiach, the salvation of God Almighty. But when most synagogue leaders heard this they ran Paul out of town on threat of death.
But the Gentiles embraced the message, because it was about them too. The Jewish Messiah was being offered for/to them as well. To cover the gentiles sins as well as the sins of Israel. Israel did not like this because it yanked the favorite seat they placed under them right out from beneath them. And put them on equal footing in regards to righteousness with the Gentiles. Both laid out flat on the ground, face to the dirt.
I believe he made it impossible to observe that which we as a people lied about keeping. As if to say....""""you think you keep my Torah?? try keeping it now that you have broken the covenant. Since you broke the covenant I will remove your blessings. The ability to keep Torah as given being one of them. Now be self-righteous, hmm?"""" He humbled Israel. And will humble the nations too, now that they have placed themselves above Israel, and God's words.
Nobody demands complete observance to something and then makes it impossible for them to achieve it. God did not make the Torah great and holy only to make it impossible for Israel to observe it. Yet, it's impossible to observe the Torah the way God gave it to us, here in exile. So this tells me that the Torah given Israel at the mountain is not the means by which he will redeem us here in the wilderness before he gathers us home. Messiah must have spoke and taught a Torah that was not identically observed as given back on the mountain. And his witness and testimony in
John 6 definitely play this out.