A good clue to what the Cross gave, gifted (grace, charis) the New Covenant believers is found here:
Luke 7
28"I say to you, among those born of women there is no one greater than John; yet he who is least in the kingdom of God is greater than he."
If John said the greatest in the Old Covenant was not as great as the least in the new Covenant, we must find out what the difference is. It must be a related to another clue here:
Hebrews 4
8For if Joshua had given them rest, God would not have spoken later about another day. 9There remains, then, a Sabbath-rest for the people of God; 10for anyone who enters God’s rest also rests from their works,e just as God did from his. 11Let us, therefore, make every effort to enter that rest, so that no one will perish by following their example of disobedience.
Joshua was one of the few successful leaders in the Old Covenant. He managed to complete the full cycle of what ever the phases were that was required of a believer's life in the Old Covenant:
1. leave dependence on the world, abandon Egypt
2. follow dependence on God, switch loyalty to God
3. be exposed to God's teachings, drink from the Rock
4. understand the mission goal: inherit the Promised Land
5. be a blessing to the world: be a light to the Gentiles, who would see God and turn to and glorify Him (honour God)
Yet Joshua never gave Israel closure. There remained for Israel to be obedient with the Jubilee Laws, laws made in the context of the Land, until the Land was cleansed of Adam's curse. Finally, Israel disobeyed and was exiled from the Land.
The Land is important, like a secret ingredient that makes a superhero powerful, the Land made Israel, God's superhero, powerful.
Non-observance affected even the surrogate tenants, when the Land was sub-let to people who were not formally in covenant:
2 Kings 17
24The king of Assyria brought men from Babylon and from Cuthah and from Avva and from Hamath and Sepharvaim, and settled them in the cities of Samaria in place of the sons of Israel. So they possessed Samaria and lived in its cities. 25At the beginning of their living there, they did not fear the LORD; therefore the LORD sent lions among them which killed some of them. 26So they spoke to the king of Assyria, saying, “The nations whom you have carried away into exile in the cities of Samaria do not know the custom of the god of the land; so he has sent lions among them, and behold, they kill them because they do not know the custom of the god of the land.”
27Then the king of Assyria commanded, saying, “Take there one of the priests whom you carried away into exile and let him go and live there; and let him teach them the custom of the god of the land.” 28So one of the priests whom they had carried away into exile from Samaria came and lived at Bethel, and taught them how they should fear the LORD.
What went wrong with Israel's attempt to inherit the Kingdom of God?
A clue is found here:
The Shadow of Christ in the Law of Moses | The Works of John Frame and Vern Poythress
Quote
We may return to the same conclusion that we reached before: the sacrifice of animals is inadequate to achieve final cleansing, nor can it cleanse anything more than the copies of heavenly things. Then who will bring the definitive sacrifice? A man must do it. A similar point is made indirectly in Num. 35:33-34: “Do not pollute the land where you are. Bloodshed pollutes the land, and atonement cannot be made for the land on which blood has been shed, except by the blood of the one who shed it. Do not defile the land where you live and where I dwell, for I, the LORD, dwell among the Israelites.” When a man had shed blood, the man must die. But there is one exception, when the blood of the death of the high priest releases a manslaughterer to return home (Num. 35:25-28). The blood of the high priest has special value. In agreement with this principle, Zech. 3 uses all the symbolism of a defiled human high priest Joshua and then speaks mysteriously of the Branch in connection with which “I will remove the sin of this land in a single day” (Zech. 3:9).
The Cross cleansed the Land and the Land was Christ, who identified with Israel. Believers, could rest IN Christ, the Israel of God. He was the Promised Land, foreshadowed in the Old Testament. Mankind was cleansed of the curse of Adam. A believer could be a blessing to the world as long as he was a tenant IN Christ, something the OT believer, even Spirit filled, like Samson, could not.
Look at the phases in the New Covenant believer's life:
1. Believers had to leave Egypt, dependence on the world
2. They had to follow God, switch loyalty to God
3. Drink from the Rock, hear God's teachings
4. Be pleasing to God, unlike the Israelites who perished in disobedience to the command to overcome the Canaanites, be born again, see the value in serving others
5. See the Kingdom of God, see the treasure that does not rust
6. Obey when they heard His call to leave self, heed God's call to conquer the Canaanite (leave dependence on self, attempts at self preservatio/n)
7. Enter the kingdom of God, continue in valuing self sacrifice, continue abandoning serving self
8. Inherit the kingdom of God, function in sanctified mode, chayei olam, doing works that men saw and gave God glory for.
I will leave the last part out, as it is a VERY HARD teaching. Those who have ears will understand. You are the ones ready for meat, have left milk food. Able to follow through to the logical conclusion...