1. The report of the spies and the resultant controversy
Parshat Shelach relates the tragic account of the failed mission of the meraglim – the spies. These spies were sent to the Land of Cana’an in order to gather intelligence to be used in the conquest of the land. The spies returned and delivered their report to Moshe, Aharon and the nation. Initially they acknowledged the fertility of the land. However, they expressed doubt and anxiety regarding its conquest. One of their members – Kalev – challenged their timidity and expressed confidence that with Hashem’s support they would easily take possession of the land.
Kalev’s opposition only provoked the other spies to become even more strident in their claims. They further described the might of the nations occupying the land and added a new claim. They revised their report of the land’s remarkable fertility and now described the land as uninhabitable by any people other than those reared and acclimated to its environment. The intense negativity of the spies raised a general panic among the people. The nation became despondent and a movement emerged to return to Egypt.
Yehoshua stepped forward. He had also participated in the spies’ mission. He took Kalev’s side and assured the people that the land was indeed a treasure and that with Hashem’s assistance it would easily be possessed. Yehoshua’s comments only evoked more confusion, panic and ultimately open rebellion.
And Hashem spoke to Moshe: How long will this nation rebel against Me? How long will they not be faithful to me despite all of the signs that I have performed in their midst? I will strike them with pestilence and drive them out. And I will make from you a greater and mightier nation. (Sefer BeMidbar 14:11-12)
2. Hashem’s changing response to the rebellion and Moshe’s pleas
At this point, Hashem speaks with Moshe and announces that the nation will be destroyed and a new more worthy nation will be formed from Moshe and his descendants. Moshe beseeches Hashem to spare the nation. As a result of Moshe’s petition on the nation’s behalf, Hashem announces that the people are forgiven. However, immediately after announcing that He has forgiven the people, Hashem declares that the current generation that has failed to place its trust in Hashem will die in the wilderness. Their children – the next generation – will enter the Land of Cana’an and conquer it. In short, within a few passages Hashem takes three different positions. Initially, He declares that He will destroy the nation. Next, He announces that the nation has been forgiven. Finally, He decrees that the current generation – that was apparently forgiven – will die in the wilderness and only their children will enter and posses the Land of Cana’an. How can these changes in Hashem’s position be explained? Furthermore, why will Hashem destroy the current generation after He has agreed to forgive their sin?
… And the nations that have heard report of You will say: Hashem lacks the ability to bring this nation into the land that he promised to them and He destroyed them in the wilderness. (Sefer VaYikra 14:15-15)
3. The meaning of Moshe’s petition
In order to understand Hashem’s apparently shifting response to the evolving revolt of Bnai Yisrael and Moshe’s pleas it is important to carefully analyze Moshe’s petition. Moshe’s plea is actually composed of two distinct components. It includes an argument on behalf of Bnai Yisrael and an appeal to Hashem’s mercy. The argument has two components:
• Moshe argues that the relationship between Hashem and Bnai Yisrael was firmly established through the nation’s redemption from Egypt. The nations of the region had heard reports of the destruction of the Egyptians and the journey of Bnai Yisrael through the desolation of the wilderness. These nations now are aware that Bnai Yisrael was rescued from Egypt and preserved in the wilderness by a mighty deity.
• If Bnai Yisrael is destroyed in the wilderness by Hashem, these nations will not assume that this is the result of a rebellion against Hashem. Instead, the nations will conclude that although powerful, Hashem is not omnipotent. He lacks the power to lead Bnai Yisrael in the conquest of the Land of Cana’an. Therefore, rather than allowing them to be defeated in their battle with the nations occupying the land, He Himself destroyed Bnai Yisrael in the wilderness.
In other words, Moshe argued that the redemption from Egypt was more than the fulfillment of a promise to the Patriarchs of Bnai Yisrael. It was a revelation to humanity. It revealed the existence of an omnipotent G-d that interacts with humanity. He enters into relationships with individuals and nations and He fulfills His promises. The destruction of Bnai Yisrael would nullify this revelation. Hashem would no longer be perceived as omnipotent or capable of fulfilling His promises.
This argument combined with Moshe’s appeal to Hashem’s mercy succeeded in securing forgiveness for the nation. However, this forgiveness had limitations.
And I also will proceed with them harshly. I will bring them into the land of their enemies and then either their uncircumcised heart will be humbled or their sin will be expiated. And I will recall My covenant with Yaakov. Furthermore My covenant with Yitzchak, and furthermore My covenant with Avraham I will recall. And I will recall the Land. (Sefer VaYikra 41-43)
4. Exile and the promise of redemption
The above passages are the conclusion of the blessing and curses outlined in Sefer VaYikra. Hashem tells Bnai Yisrael that their destiny in the Land of Israel will be determined entirely by their behaviors. If the nation is faithful to the Torah, then it will be rewarded with remarkable blessings. However, if the people abandon the Torah then they will be punished with increasingly harsh consequences. Ultimately, stubborn refusal to repent and return to the Torah will be punished by dispossession of the Land and exile. Even in exile Bnai Yisrael will not have peace. The nation will be hounded and persecuted by their enemies.
In the above passages Hashem promises that He will not entirely abandon His nation. They will be redeemed from exile and returned to the land that Hashem promised with a covenant to the patriarchs. The first of these passages is translated as suggested by Nachmanides. According to Nachmanides, there are two circumstances under which Bnai Yisrael will be redeemed. One path to redemption is through repentance. The passage describes this as the restoration of humility to the uncircumcised heart. The second path is through expiation of the nation’s sins. Expiation does not involve repentance. It simply means that the sin of the nation has been punished and through enduring this punishment the nation’s sin is in some way neutralized.
This concept of expiation is not easily understood. It seems strange that redemption can come about through expiation of a sin and without sincere repentance. However, some insight into the concept of expiation is provided in the passages that follow. These passages focus on Hashem’s covenant with the Patriarchs. The apparent relevance of the covenant is that it established an eternal relationship between Hashem and His nation. Therefore, the complete destruction of Bnai Yisrael can never occur. Every exile must come to its conclusion. Redemption may be delayed but it is inevitable. Expiation provides a vehicle for forgiveness and redemption when repentance is not present. Suffering and exile can be ended immediately through repentance. However even without repentance, every exile must come to an end with the ultimate redemption of Bnai Yisrael. Without repentance the exile will be prolonged and may even seem interminable. Redemption will arrive only after the people’s sins have been completely expiated.
And Hashem said: I have forgiven according to your word. However, by My life and as the glory of Hashem fills all the land, all of the men who see My glory and My wonders that I performed in Egypt and in the wilderness and have tested Me these ten times and not obeyed My voice, they will not see the land that I promised to their father. All that rebel against Me will not see it. (Sefer BeMIdbar 14:20-23)
5. Moshe secures Hashem’s pardon but not His forgiveness
The above passages describe Hashem’s response to Moshe’s entreaties. He tells Moshe that He will forgive the people “according to your word.” In other words, Hashem accepted Moshe’s argument. When Moshe’s argument is considered carefully, it is clear that Moshe did not argue that Bnai Yisrael deserved to be forgiven. He did not argue that the sin was excusable or understandable. Neither did Moshe attempt to minimize the sin. Instead, Moshe argued that despite their sin, the nation should not be destroyed. Too much would be lost were Bnai Yisrael destroyed. The revelation of the redemption from Egypt would be nullified and the nations of the region would return to ignorance and darkness. This is an argument for pardoning Bnai Yisrael not for their forgiveness.
Hashem told Moshe that He is responding to his entreaties. He will pardon the nation. He will not forgive their sin. The people will be punished. The generation that rejected Hashem will perish in the wilderness. They cannot be rescued from their wanderings in the wilderness. They have not repented. However, the nation’s ultimate rescue and redemption is inevitable. With the punishment and passing of this flawed generation, the nation’s sin will be expiated. The next generation will enter the land and possess it.
 Rabbaynu Moshe ben Nachman (Ramban / Nachmanides), Commentary on Sefer VaYikra 26:41-42.