Answer: A person feels that he is in exile after having been on a high level, and so he can understand that now he has descended into exile. Exile is a descent, after a person has understood something, felt something, has been in contact with the Creator, now he feels that he is detached from all this at least to some extent.
The levels of the forefathers: Abraham, Isaac, and Jacob, about whom the Torah tells us, are the levels of understanding, attainment, the feeling of bestowal, the attributes of the Creator, His revelation. While the descent into the exile in Egypt is already the hardening of the heart, which is felt after a person has attained a state called the “forefathers” (the most initial state).
While Lo Lishma is the initial level of a person who studies and tries to rise above all the states he feels, he is still in his egoistic intentions. He dreams about attaining bestowal and feels the value of this attribute and wants to detach from himself. But he wants this detachment for himself too, feeling how good it will be. This feeling of yearning for bestowal but still acting for his own good is called Lo Lishma.
But it is on condition that he values bestowal not because it helps him detach from the corporeal troubles or in the hope of receiving some spiritual reward or achievement. He wants to be in bestowal because this is how the Light operates on him. A person doesn’t even know what it means to be in bestowal. But new attributes are born in him and such vessels and inclinations are stabilized, which force him to value bestowal. He doesn’t even know where it comes from, but it is the result of the influence of the Light that Reforms.
Then this inclination becomes more and more conscious and a person begins to hold on to it by himself. Eventually he reaches a state in which he only wants bestowal, by cutting himself off from all personal interests.
In order to do that, a person must go through the hardening of the heart many times and encounter many obstacles. He is shown that there are things in life that are dear to him and from which he cannot detach himself, to what extent he still worries about them and cannot ascend above his egoistic love for some people or passions for different phenomena. At the same time, he sees to what extent he cannot ascend above his hatred towards someone or something.
The Light helps him clarify this, and eventually by much work and praying, a person tries to ascend above all that and nearly reaches bestowal. Then the upper Light completes this level for him, as it says: “I have labored and I found.”
The main thing is to hasten his advancement by intensively working in the group. Everything depends on the environment.
From the 1st part the Daily Kabbalah Lesson 11/27/12, “Introduction to the Study of the Ten Sefirot”