Peace to you Sun Tzu and welcome to the forums.
May I answer your question for you?
All those verses you have quoted do indeed APPEAR to show that the law of moses was abolished in the life and death of Christ. But please re read them in the context they were written.
The number one rule of any Bible study, is that you do not pluck a verse out and use it to build an arguement around.
Any of us could do that and we could create a complete belief system around that one verse, which is anything but what the context of the verse is saying. So with that rule in mind and as briefly as I can possible make it let's relook at those verses.
Ephesians 2:13-15
Paul is here talking not to Jews but to Gentiles (The Ephesians) about their place in Christ's kingdom. He points out in the early verses of the chapter that the Jews had called them "uncircumcised" and separated from the covenant promise of God. Now, in Christ that has all changed.
Did he mean that Christ had changed the Law? no of course not, for Paul knew Christ's words that He had come to fulfill it and not to change it. Paul as Saul, had been trained as a Pharisee. He knew the Law inside and out, back and front and yet to these Gentiles who were struggling about their place in God's kingdom, he a jewish convert to Christianity declares , that " by abolishing in his flesh, the law with it's commandments and regulations. His purpose was to create in himself one new man our tof the two, thus making peace."
He then tells them that consequently, you are no longer foreigners and aliens, but fellow-citizens with God's people and members of God's household, BUILT ON THE FOUNDATION OF THE APOSTLES AND PROPHETS (the law) WITH CHRIST HIMSELF AS THE CHIEF CORNERSTONE.
You see Sun Tzu, no where did he literally mean that Jesus took away the Law, but the Law had it's limitations and in Christ, the Law was fulfilled and the limitations removed.
Hebrews 7:18-19
the entire book of Hebrews is a discussion on how Christ fulfilled the law. It is a book written not to Gentiles, but to Jewish believers who needed to know how Christ's death and resurrection fulfilled the Law. and again how He was the one the Law pointed to.
he fulfilled the requirements of the law in a way the Law itself never could. In these verses the author (widely accepted as Paul) has been discussing that perfection in God's sight could never be achieved by the Law. In Hebrews 7:11 he describes that another priest must come and in the background of jewish understanding in verse 12, he says that if a new priest comes, so also will there be a change in the law. He then introduces Jesus in the verses you have quoted as the new priest and states that the former regulations are set aside (not abolished)
Note in chapter 7:26 WHY this high priest met our needs ... because he was holy, blameless, set apart from sinners and exalted above all others. Whereas the old law required a new high priest every year and even when the required sacrifices were presented at the mercy seat, and all Israel prayed that God would forgive them (for there was no guarantee), with this High Priest, there would no longer be a need for a daily or annual sacrifice, for in Him all the requirements of the Law were met. It was a new covenant relationship with God and man
Now please read chapter 8 fully and understand the need for a new covenant and a new high priest. and especially read God's words in Hebrews 8:8, which are quoted from Jeremiah 31:31-34
The time is coming, declares the Lord, when I will make a new covenant with teh house of Israel and the House of Judah. It will not be like the covenant I made with their forefathers, when I took them by the hand and led them out of Egypt, because they did not remain faithful to my covenant, and I turned away from them declares the Lord.
I will put my laws in their minds and write them in their hearts. I will be their God and they will be my people. No longer will a man teach his neighbour and or a man his brother, saying "know the Lord". for they will all know me, from the least of them to the greatest. For I will forgive their wickedness and will remember their sins no more."
If you take the verses you gave and quote them, it does appear that paul is saying those things, but in context and realising 1. he comes from a very Jewish background and knowledge of the Law, 2. He is talking to two very different groups of christians in the very early christian church.. the Jews in one letter and a Gentile group in the other 3. In context he is discussing the law and it's implications with both groups and how it affects them, you can see that in no way was he throwing the law out and going against Jesus' words in matthew