God chose them...but as Tevya asked God: "We are the Chosen People but once in a while can't You choose someone else?"
When we accept Messiah, we are adopted into the family of Abraham. We are grafted into the vine. Therefore, we too become adopted into the family of the Chosen ones. We don’t replace them, we are joined to them exactly like any adopted child becomes a part of the family. The same rules apply to all.
I personally don’t follow the rabbinic laws but I do hear some awwesome wisdom from them. I don’t follow their commentary books. But I do do my best to follow God’s word in his Torah, prophets and writings.
I do have a question though. If wheat and leaven are removed from the home, what is the grain that is used to make matza?
Jews claim the following verse makes them the chosen people.
1 Now the LORD had said unto Abram, Get thee out of thy country, and from thy kindred, and from thy father's house, unto a land that I will shew thee: 2 And I will make of thee a great nation, and I will bless thee, and make thy name great; and thou shalt be a blessing: 3 And I will bless them that bless thee, and curse him that curseth thee: and in thee shall all families of the earth be blessed. (Genesis 12:1-3)
But hold on, Paul clarifies in Galations who exactly is chosen.
16 Now to Abraham and his Seed were the promises made. He does not say, And to seeds, as of many, but as of one, And to your Seed, who is Christ. 17 And this I say, that the law, which was four hundred and thirty years later, cannot annul the covenant that was confirmed before by God in Christ, that it should make the promise of no effect. 18 For if the inheritance is of the law, it is no longer of promise; but God gave it to Abraham by promise. (Galatians 3:16-18)
If you are not in Christ, then you are not a child of the promise.