I dont know how the jewish people still think they under the old covenant when their temple was destroyed, but they still practise the laws of Moses, well some of it, obviously cant keep them all. For example circumcision, which was required under the old covenant as the first thing Abraham did. Covenant means 'to cut' and every male child on the eighth day is circumcised...thats just what theyve carried on doing.
Not saying its right or wrong, but they still do it.
I dont believe God has cast away his people Israel who he foreknew. He is patient with them, imagine knowing all about God yet not acknowledging His son. Today I dont believe its necessarily because they actively refuse, but any child growing up jewish has their parents and rabbis teach them that Jesus is not the messiah, or they are shielded from the truth. Their bibles do not include the new testament...back in the day they didnt have it, and when it was collated, it was all in greek. Thankfully there are Hebrew translations available to them and the word is spreading. The book of Hebrews was written for them, (all israelites) but as far as I know it was in greek which was the common language of the time.
Why did they call their nation Israel and not Judah, well the thing with Judah tribe was they kind of had the lot of land with Jerusalem where the temple was located, with the land its all about location, location, location. Israel encompasses all the tribes not just Judah, but judah is the one thats contentious. They were able to observe more as they didnt have far to go to offer sacrifices, the rest of the tribes had to travel into Jerusalem to celebrate the feasts and make the sacrifices. Judah was the tribe from which kings came.
