Why does it say the "New Covenant" Jesus made is only for the Jews?
Hebrews 8:8 - But God found fault with the people and said: “The days are coming, declares the Lord, when I will make a new covenant with the people of Israel and with the people of Judah.
Sadly, to many people do not look at the Greek text to see if the English context is the same of the English context.
Now when I say "new" in English, there are two possible ways of understanding this word: -
The object is brand new with respect to age, i.e. if it was a car, it has just come of the assembly line into your possession.
The object is new with respect to when the object was acquired, i.e. if it is a car, I have purchased a preloved car to replace the one I have traded in such that I can describe the car as being "my new car."
Now if I was using the Greek language to say "new with respect to age" I would use the Greek word "Neo." G:3501.
Now in the quoted verse, Heb.8:8 the Greek word translated as "new" in our English Translations is the Greek word, " καινήν, kainēn" and the greek Root this Greek word is derived from is: - "καινός kainos G:2537" and its meaning is given as :- "Of uncertain affinity; new (especially in freshness; while neos is properly so with respect to age -- new" such that we can understand that the Heb. 8:8 text is actually saying: -
“The days are coming, declares the Lord, when I will make a refreshed covenant with the people of Israel and with the people of Judah."
Now if we consider the reference to Jer. 31:31, we will read that the covenant will be make like new again with the House of Israel and the House of Judah, not identically like the covenant that God made with Israel at Mt Sinai which they rebelled against, but this time, the covenant that I will make with the house of Israel after those days, says the Lord: I will put My law in their minds, and write it on their hearts; and I will be their God, and they shall be My people. No more shall every man teach his neighbor, and every man his brother, saying, 'Know the Lord,' for they all shall know Me, from the least of them to the greatest of them, says the Lord. For I will forgive their iniquity, and their sin I will remember no more."
The Mt Sinai Covenant is often referred to as The Kingdom of Priests, A Holy Nation and My Possession among the Nations Covenant.
Christ during His first advent did not make any "Neo"/new covenants with His disciples, but rather Christ refreshed the Ancient Covenant from the time of Adam which gives all who abide in the refurbished covenant, Salvation for all who believe.
In Matt. 13:52 Christ made a reference to this ancient Salvation Covenant from the Time of Adam in which Christ's sacrifice on the cross altered the process by which our salvation will be gained through our belief in Him.
Oh well, sadly a desire for something new will not get us our salvation as the only difference is how our sins are redeemed by God. This is not gained by our terms, but by the terms that God has now had put in place by Christ. The Salvation is still the same as it was back during the time of Adam, however the process by which this Salvation is obtained has been altered and it requires us to repent of our sins and to humble ourselves and accept His Salvation with Grace.
Shalom