NOTES for Deu 32:26-52
The fate of the people on the land promised to them by God depends on their spiritual condition. That is the main message of the hymn we find in the closing part of the Book of Deuteronomy. If the external events of Jewish history always reflected the spiritual condition of the people, they would have lost their land very quickly, which is exactly what the hymn says.
Here we hear a truth well known to us from the New Testament books, and known to the Jews even before the coming of Christ: fallen man, by definition, deserves nothing good. This is not because he must necessarily be punished for sins, but because he is not capable of earning anything. To earn something, one must serve, serve God, and serve Him as He should be served. In other words, one must do what no one in the fallen state can do or knows how to do, and often, deep in the heart, does not especially want to do, although few believers are ready to admit this to themselves.
The people of God are no exception. They are God's people not by virtue of any national characteristics, not because the laws of the fallen world do not apply to them, but because God has a special plan for them, which God carries out despite all obstacles. If the people can remain on their land for any length of time, it is only because God is working with them on that land, trying to make them into the communal people He intended. Without this work, the catastrophe known as the Babylonian captivity could have happened much earlier.
God does not punish the people for their sins; the people punish themselves by coming face to face with the consequences of their choices and their actions. God, on the contrary, slows the arrival of those consequences as much as possible, but only to the extent that such slowing fits into His own plans. In the end the moment will come when the formation of the people as a community will require the people to meet the consequences of their spiritual choice face to face, and then catastrophe will break out.
For now, at the time the hymn mentioned above was written, alternatives are still possible. The catastrophe could perhaps still be avoided altogether, but of course only on the condition of focused and consistent spiritual work, which is what the Book of Deuteronomy, and the whole Torah with it, speaks about.