Isaiah 53 needs to be read in the full context of the whole chapter in order to understand vs. 7 as the whole chapter is fulfilled through Christ as being a Lamb brought to the slaughter as Jesus did not open His mouth as the court would not believe Him anyway so He stayed silent, Matthew Chapter 26; Mark 15:1-5; Acts 8:26-33. God's plan of salvation was through His only begotten Son Christ Jesus before the foundation of the world as being the unblemished Lamb brought to the slaughter, but not like all the other dumb lambs that God had no delight in as it was done all in vain every year on Passover. This Lamb of God being Jesus would redeem the world of their sin once and for all through the shedding of His own blood, Matthew Chapter 27.
The Torah is only the first five books of the Bible from Genesis to Deuteronomy written by Moses so there was no new Torah being taught in the NT, but only the grace of God and His plan of salvation through Jesus before the foundation of the world, Ephesians 1:3-7; 2:8; In the book of Isaiah the messianic prophecies are clearer and more explicit about Christ then any other OT writings.
If you start with Isaiah Chapter 1 God is very wroth with the nation of Israel, (except for a small remnant), going as far as calling them a sinful nation who have gone backwards forsaking God. Even their sacrifices were being done in vain as God said in vs. 11 To what purpose is the multitude of your sacrifices unto me? saith the LORD: I am full of the burnt offerings of rams, and the fat of fed beasts; and I delight not in the blood of bullocks, or of lambs, or of he goats. 12 When ye come to appear before me, who hath required this at your hand, to tread my courts? 13 Bring no more vain oblations; incense is an abomination unto me; the new moons and sabbaths, the calling of assemblies, I cannot away with; it is iniquity, even the solemn meeting. This is also written in Hebrews 10:1-39 as the book of Isaiah is a shadow/prophecy of the coming of Messiah being Jesus who was the Lamb being brought to the slaughter who did not open His mouth during His trial. They witnessed all that Jesus taught from the OT and saw the signs and wonders of God through Him so Jesus had no need to open His mouth to defend Himself. The Jews called Him a blasphemer for saying He and the Father are one. This is also found in Matthew Chapter 26; Mark 15:1-5; Acts 8:26-33.
The Jews never recognized Jesus as Messiah as they were expecting a goodly priestly king that would come and literally sit on the throne of David and not just some carpenters son from Nazareth as Nathaniel asked Philip, can anything good come from Nazareth and Philip said to him, come and see, John 1:46.
You said you have read the NT, but it seems you have no understanding of what is written as what Jesus taught was from the Torah (first five books of the Bible) and from the rest of the OT. Everything Jesus spoke was given Him by God, John 12:44-50.
