Then we are in agreement. Salvation did come from the Jews -- all thirteen of them. But that's where it stopped. The rest was done by the "other sheep." The "sheep" who took the New Covenant and spread the name of God of Abraham throught the world.
The people of the Old Testament have not accepted the New Testament (not yet anyway, although hope exists) but are defiant as they were with the First One.
So, the "other sheep," who are the backbone and carriers of the New Covenant, have no reason to dwell, seek, imitate, copy, or do anything the followers of the obsolete Covenant do, lest they make the New Covenant obsolete as well.
You have a misunderstanding of the covenants. You seem to confuse the old covenant, ratified at Sinai, with the entire collection of books called the "old testament". They are not one and the same. Paul based all of his understanding upon the only scripture he knew...the books of the "old" testament.