In order to enter into a covenant with God, one must choose to do so. Though Israel is still under the Old Covenant, it hasn't accepted the terms of the New Covenant, and therefore isn't within it. So, God created a New Israel, the Church, to accept the terms of the New Covenant, while the Old Israel remains under the Old.
God had Abraham set up the sacrifice and God promised his descendants the land of Canaan as a permanent possession and God consumed the sacrifice and required nothing from Abraham to receive this promise. The promise to the nation coming out of Israel was conditional that they would be blessed for walking in Gods ways and cursed even to expulsion if they went bad. God kept the conditional covenant too. In the law when God promised to wipe them out he reaffirms the 1st promise to Abraham that was unconditional. Deu 4 25 “When you beget children and grandchildren and have grown old in the land, and act corruptly and make a carved image in the form of anything, and do evil in the sight of the LORD your God to provoke Him to anger, 26 I call heaven and earth to witness against you this day, that you will soon utterly perish from the land which you cross over the Jordan to possess; you will not prolong
your days in it, but will be utterly destroyed. 27 And the LORD will scatter you among the peoples, and you will be left few in number among the nations where the LORD will drive you. 28 And there you will serve gods, the work of men’s hands, wood and stone, which neither see nor hear nor eat nor smell. 29 But from there you will seek the LORD your God, and you will find
Him if you seek Him with all your heart and with all your soul. 30 When you are in distress, and all these things come upon you in the latter days, when you turn to the LORD your God and obey His voice 31 (for the LORD your God
is a merciful God), He will not forsake you nor destroy you, nor forget the covenant of your fathers which He swore to them.
God will not forget this covenant made with the fathers. Psalm 105
He
is the LORD our God;
His judgments
are in all the earth.
8 He remembers His covenant forever,
The word
which He commanded, for a thousand generations,
9
The covenant which He made with Abraham,
And His oath to Isaac,
10 And confirmed it to Jacob for a statute,
To Israel
as an everlasting covenant,
11 Saying, “To you I will give the land of Canaan
As the allotment of your inheritance,”
12 When they were few in number,
Indeed very few, and strangers in it.
Finally the prophecy about Jesus in Luke 1
67 Now his father Zacharias was filled with the Holy Spirit, and prophesied, saying:
68 “Blessed
is the Lord God of Israel,
For He has visited and redeemed His people,
69 And has raised up a horn of salvation for us
In the house of His servant David,
70 As He spoke by the mouth of His holy prophets,
Who
have been since the world began,
71 That we should be saved from our enemies
And from the hand of all who hate us,
72 To perform the mercy
promised to our fathers
And to remember His holy covenant,
73 The oath which He swore to our father Abraham:
74 To grant us that we,
Being delivered from the hand of our enemies,
Might serve Him without fear,
75 In holiness and righteousness before Him all the days of our life.
This promise of Israel being Holy and serving the LORD is accomplished at he 2nd coming when the LORD saves them from destruction and it is seen in ZEch 14. This si the day the lORD is king over all the earth and delivers them from their enemies. This is the moment Jesus is revealed to them like Joseph was to his brothers and they will bow down and in that day recognize Jesus as God and king. Study ZEch 14 and note in the day the LORD is king over all the earth life goes on as the Mt of Olives has split in two and the river flows year round. Also the nations must now come and keep the feast of tabernacles or they get no rain. It also notes at that time no more Canaantites will enter the house of the LORD.