Answer: The last level of the Tower of Babel is the biggest ego that exists in us. And you must reach it in order to rise to the world of Infinity, because you can only rise there through a big ego.
Question: But the model of the Tower of Babel is the model of sin. How can you use the human sin to arrive at the biggest Light?
Answer: This can be done because they are connected. When you reach the biggest sins, you merit the biggest Light.
Question: So I need to sin in order to come to the biggest Light?
Answer: That is right.
Question: So, you are pushing people to sin?
Answer: Right now I exist in a small point of this world and I want to attain a higher degree. But I am unable to do anything with the ego that I have now, because my ego is small, there is just enough to use in this world. This is why I need to reveal a big ego, let us say -100 kg (the minus is there to show that this refers to ego). Then I correct it into +100 kg of bestowal, and this way I attain correction.
And on a higher degree, I will have one ton of ego, which I will correct into one ton of bestowal.
And this will continue forever: one against the other. You sin, correct it, and arrive at the Light. Again you enter the ego, correct it, and again you attain the Light. This is how one advances in the spiritual world.
You must reveal your ego, because ego is the material where the spiritual world becomes revealed under the condition that you correct it from reception to bestowal. It is written that: “There is no righteous person in the world, who has done good deeds without having sinned.” This is why we need the revelation of the ego.
But we never work on revealing a big ego, evil, in us; on the contrary, we aspire towards the property of love and bestowal above and in spite our egoism. But when we succeed in this and acquire the property of bestowal, the egoism immediately grows, so we will rise above it once again. And this way we move ahead on two legs, the right line, bestowal, and the left line, reception.
From the Kabbalah for the Nation Lecture 11/23/10