Take some time to study Romans chapters 9 through 12.
WITHOUT ANY PRECONCEIVED IDEAS.
Nehemiah6 you know me pretty well, I've be through the entire book of Romans multiple times.... Romans is what helped me see that the flesh descendants were never the children of the promise.
The flesh descendants had their purpose, the law was given through them, Christ came through them, the promises were spelled out through them and the word of God was given to their care. That's all they got and that's spelled out in Romans 9: 4-5.
(Rom 9:4) Who are Israelites; to whom pertaineth the adoption, and the glory, and the covenants, and the giving of the law, and the service of God, and the promises;
(Rom 9:5) Whose are the fathers, and of whom as concerning the flesh Christ came, who is over all, God blessed for ever. Amen.
They could have received the promise land IF and ONLY IF, they obeyed EVERY single commandment. This is not even really an IF because NOBODY can do that.
For they are NOT all Israel that came out of Israel. The first Israel in that statement is the true Israel of God, the second Israel in the statement is the flesh descendants. The flesh descendants were never chosen, it's always bee the spiritual descendants. And this is backed up from cover to cover throughout the bible.