When God promised Abraham the blessing of life it was His answer to the sin and death that Adam had brought into the world. That promise was to be realized through Mashiach. Abraham and his family were to receive the fulfillment of the promise of the blessing of life on behalf of all the families of the earth by being in the place, together with Mashiach, that God said for them to be in order to receive it.
When Abraham doubted and said, "How do I know that I will inherit the Land?" it seemed that he doubted himself and his family and their ability to meet the condition for receiving the fulfillment of the promise by being fully in the place where God told them to be in order to receive that promise. As a result of this, God made a formal covenant with Abraham to assure him. He transformed His promise into this formal covenant.
In other words, God assured Abraham by saying to him, as it were, 'as you see this covenant being kept you will be certain that you and your family will dwell fully in the place where I have called you to live, and that therefore the promise of the blessing of life will come to you and will overcome the sin and death that Adam brought into the world'.
Repentance is not possible for Adam or for any child of Adam apart from the promise of the blessing of life that God promised to Abraham. Repentance does not just mean only being sorry for a sin. It does not just mean regret, even sincere regret, nor just a change of future behavior based on regret. It means, first, actually changing the decision that caused the sin.
If, for example, I stole something it is because I decided, on some level, to steal what I stole. Yes, that decision is in the past and you can't change the past, but you can change your mind, and even though you cannot change the past, because repentance is commanded by God, even a decision you have already acted upon can be changed. You can do more than passively regret that decision. You can actively regret it. You can change it. You have the authority of God's commandment to do so. I repent of having stolen what I stole.
This means I repent of having made the decision to steal what I stole. I repent of the thinking that I chose to have before that led to that decision. I no longer want to have that thinking, not just in the future. I don't chose to have that thinking be a part of me at all, even though it was a part of me in the past. I reject that thinking and repent of it entirely. So much as God's commandment miraculously empowers me, I am changing the decision that I acted upon in the past, and though I am responsible for having acted upon it, I now renounce that decision. It was wrong thinking and a wrong decision.
And because the decision is changed it is possible that the act of the sin itself can be changed. Of course neither Adam, nor any child of Adam, can do this on their own. It involves a miracle. And only God can work miracles. This is exactly what God promised to do when He promised Abraham to bring through him and his family the blessing of life in place of the sin and death that Adam brought into the world.
Can the act of sin, the act of any sin, actually be changed, so that the sin no longer exists? To be forgiven or pardoned for a sin implies the idea of the sin no longer being regarded as a sin. However, will the consequences of a sin be changed if and when a sin is pardoned? And while all sin is ultimately against God, and can therefore ultimately only be forgiven by God, sins are also committed against other people and other creatures. How can all the sin and all the consequences of sin in the world actually ever be rectified? How can all lives actually ever be reconciled? Repentance must go far beyond regret and must seek to accomplish this. Any idea that repentance can do this without being empowered by God to do so lacks a true sense of sin, a true vision of righteousness and a true knowledge of the judgment of God against sin.
God's empowerment of repentance began with a promise which He made to Abraham that through him and through his family the blessing of life would replace the sin and death that Adam brought into the world. In order for this promise to come to them, Abraham and his family would need to believe God, and through faith in God they would need to live in the land that God set apart for the revelation of His promised blessing of life for the world. In order to assure Abraham and strengthen his faith and the faith of his family that this would happen, God made a covenant with Abraham that He would raise his family up out of bondage from a strange land and would equip them to dwell in the land He had set apart for them and would, Himself, bring them into that land.
When God gave the Torah to Israel on Mount Sinai, after bringing them "on eagle's wings" out of the land of Egypt, the land representative of Adam's bondage, He gave them the word of God by which they would be able to dwell in the land set apart for the empowerment of repentance and the blessing of life, being delivered from the realm of the bondage of sin and death. It is for this reason of repentance and faith in preparation for the fulfillment of the covenanted promise of God to Abraham and to his family, the fulfillment through Mashiach of the blessing of life for the world, that the family of Israel must live in the Land of Israel through the empowerment of the Torah.
When the family of Abraham failed to enter or dwell in the land through faith in accordance with the word of the Torah of God, the time came when God said He would make His covenant with Israel, now divided into the House of Israel and the House of Judah, anew. He would make His covenant with Israel in such a way that He would Himself write His instructions for living in the land in their hearts and in their minds, and all would know Him, so that no one would have to instruct anyone else. This new form of the family covenant of Abraham would be the assurance of the blessing of the world through them, the success of universal repentance.
For this reason, even now, for those who have this assurance of faith, it is given to look into the Torah and find the treasure of redemption. For the Torah was the way of redemption from the beginning, from the coming up out of Egypt of the family of Abraham, the way for the family of Abraham to enter into and dwell in the land in peace. And this is the way of salvation for the world. This is the covenant that God makes with the house of Israel and the house of Judah in order that the family of Abraham might know and not doubt that they will inherit the land. This is the covenanted promise that God has revealed in order that all the families of the earth might bless themselves in Abraham and in his family, through Mashiach, who brings the fulfillment of God's promise to Abraham and Sarah.
In order for repentance to undo sin in its entirety, both in its act and in its consequence, repentance must begin with the beginning of sin, the sin of Humanity as a whole, the sin of Adam. The sin of Adam was an act of rebellion by the Father of Humanity acting as a General, turning Humanity into a rebel army. Even if one has second thoughts about Adam's declared liberty from God's commandments and desires to obey God, any sin is an act of rebellion aligning that person with an army of rebels. Make no mistake, the human declared liberty to do what is right in their own eyes is war against God.
The sin of Adam in its rebellion against God enabled and empowered every sin. No sin exists in isolation. Therefore no one's repentance can exist in isolation. In repentance for each and every sin there must be repentance for rebellion against God first, before there can be repentance that undoes the decision which resulted in that given sin. We must be convinced of sin in its entirety, we must have a vision of the righteousness that sin spoiled and that would be restored if sin were undone, and we must be convicted of the judgment of God that will come upon the world if repentance does not succeed. And more, we must have a vision of the righteousness that will come when our by leaving behind the sin of Adam and joining with the host of Mashiach, repentance completely eradicates sin.
All of this is certain when Mashiach is revealed in Jerusalem, in the whole land of Israel, and in all the earth; when the spirit that he sends out from before the throne of God to come over all people rules over them. And now, even now, we can learn from that spirit of truth, if we have this faith in the promise of the renewed covenant of God with Israel. We can look into the Torah and learn, and be perfectly convinced of sin, of righteousness and of judgment. We can look, for example, into the tractate of Sanhedrin in the Talmud and learn from the sages of Israel about the illumination that can come to us concerning sin, righteousness and judgment through their consideration of the number of judges that are required in the Torah courts of Israel for the judgment of different transgressions.
7 ... I tell you the truth; It is expedient for you that I go away: for if I do not go away, the Comforter will not come unto you; but if I depart, I will send him unto you. 8 And when he is come, he will convince the world of sin, and of righteousness, and of judgment: 9 Of sin, because they do not believe in me; 10 Of righteousness, because I go to my Father, and you will not see me; 11 Of judgment, because the prince of this world is judged.