God did not renege his covenant with the Jewish people. As it was stated, the New Testament is indeed the New Covenant that God was referring to, it's just that God has largely placed a veil over the Jewish people's eyes, and that is why they haven't as whole accepted Jesus as their Messiah, until the fullness of the Gentiles or the time of the Gentiles is fulfilled. Here's some scriptures for you to mull over:
'I say then, Hath God cast away his people? God forbid. For I also am an Israelite, of the seed of Abraham, of the tribe of Benjamin.
God hath not cast away his people which he foreknew. Wot ye not what the scripture saith of Elias? how he maketh intercession to God against Israel, saying,
Lord, they have killed thy prophets, and digged down thine altars; and I am left alone, and they seek my life.
But what saith the answer of God unto him? I have reserved to myself seven thousand men, who have not bowed the knee to the image of Baal.
Even so then at this present time also there is a remnant according to the election of grace.
And if by grace, then it is no more of works: otherwise grace is no more grace. But if it be of works, then is it no more grace: otherwise work is no more work.
What then? Israel hath not obtained that which he seeketh for; but the election hath obtained it,
and the rest were blinded.
(According as it is written, God hath given them the spirit of slumber, eyes that they should not see, and ears that they should not hear
until this day.
And David saith, Let their table be made a snare, and a trap, and a stumblingblock, and a recompence unto them:
Let their eyes be darkened that they may not see, and bow down their back alway.
I say then, Have they stumbled that they should fall?
God forbid: but rather through their fall salvation is come unto the Gentiles, for to provoke them to jealousy.
Now if the fall of them be the riches of the world, and the diminishing of them the riches of the Gentiles; how much more their fulness?
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For if the casting away of them be the reconciling of the world, what shall the receiving of them be, but life from the dead?
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For I would not, brethren, that ye should be ignorant of this mystery, lest ye should be wise in your own conceits;
that blindness in part is happened to Israel, until the fulness of the Gentiles be come in.
And so all Israel shall be saved: as it is written, There shall come out of Sion the Deliverer, and shall turn away ungodliness from Jacob:
For this is my covenant unto them, when I shall take away their sins.
Romans: 11: 1-12, 15, 25-27.
The fulness of the Gentiles will be come in after the rapture of the church, and it is during the 7 year tribulation that God's focus will shift back towards the Jewish people. And Abraham's seed
is as numerous as the stars, when you factor in the many Gentiles who have accepted Christ in Christianity's two thousand year history. Those who have accepted Christ are Jews in spirit.
