Romans 15:4 puts it a little differently.
4 For whatsoever things were written aforetime were written for our learning, that we through patience and comfort of the scriptures might have hope.
 
Jesus is our peace, our hope, our life, our Saviour, God in human flesh.
Heb 8 (Cont)
6 But now hath he obtained a more excellent ministry, by how much also he is the mediator of a better covenant, which was established upon better promises.
7 For if that first covenant had been faultless, then should no place have been sought for the second.
8 For finding fault with them, he saith, Behold, the days come, saith the Lord, when I will make a new covenant with the house of Israel and with the house of Judah:
9 Not according to the covenant that I made with their fathers in the day when I took them by the hand to lead them out of the land of Egypt; because they continued not in my covenant, and I regarded them not, saith the Lord.
 
Keep in mind here that God is saying that he will make a better covenant based on better promises with man, a new one. He goes on to say that if the first covenant had been faultless there would be no reason for a second one. Then in verses 8,9 he goes on to say that this new covenant with man is not like or according to the old covenant he made with their forefathers when he led them out of Egypt. Watch how many times he repeats in the 4 verses going from the words, first, second, new and not according to the old covenant. He is showing clearly that he is instituting a new covenant with mankind.
Heb 8 (Cont)
 
I will be adding to these pages as time goes on. The word of God is a deep book and an incredible book. There is much to be said on these issues but always remember that God is a faith God and faith pleases him.
10 For this is the covenant that I will make with the house of Israel after those days, saith the Lord; I will put my laws into their mind, and write them in their hearts: and I will be to them a God, and they shall be to me a people:
11 And they shall not teach every man his neighbour, and every man his brother, saying, Know the Lord: for all shall know me, from the least to the greatest.
12 For I will be merciful to their unrighteousness, and their sins and their iniquities will I remember no more.
13 In that he saith, A new covenant, he hath made the first old. Now that which decayeth and waxeth old is ready to vanish away.
 
So we see in the closing verse that the old covenant which God made with Israel decays and waxs old and is vanishing away. Jesus came and fulfilled the law and established a much better covenant even though it was the same covenant that he had with Abraham, a covenant by faith in him and Abraham believed God and it was counted to him for righteousness.
So just walk in
5 Trust in the LORD with all thine heart; and lean not unto thine own understanding.
6 In all thy ways acknowledge him, and he shall direct thy paths.