Musar for Shabbat 178:10

But he also alludes hereby to an awesome phenomenon. And that is: If a man does not do evil to himself, who can do evil to him? For the truth is that everything that happens to a man in this world, both for the good or for the bad, is brought about by the man himself. As it relates to our subject, the descent to Egypt, its first cause was Abraham's saying [to the Holy One Blessed be He] (Genesis 15:8): "How do I know that I will inherit it?" and His responding (Ibid. 13): "You will surely know, for your seed will be a stranger in the land [Egypt], etc." And Chazal have said (Shabbath 89b): "Jacob should have gone down to Egypt in iron chains, but his merit availed him to be honored by being brought honorifically to his son who reigned in Egypt.

After all וימי חייהם הבל לפניך, "the days they sojourned on earth are as nothing before You!" Our sages have stated that "anyone who leaves behind him on this earth a son who is a Torah scholar may consider himself as though he were still alive." Even taking this fact into consideration, what good is it, since when we arrive in the World to Come and have to account for our conduct before You ימי חייהם הבל לפניך "the days of their lives are accounted as nothing?" In Psalms 36,7 man and beast are equated, i.e. אדם ובהמה; on the other hand Isaiah 63,16 states: כי אתה אבינו כי אברהם לא ידענו וישראל לא יכירנו, "You are our father for Abraham did not know us and Israel did not recognise us." The Talmud Shabbat 89b discusses this. It is well known that the word אדם is used when describing the spiritual aspect of man, whereas the exterior part of man is described as בשר אדם. Man is also called בהמה in the context of his body not being basically different from that of the other creatures in the animal world.

All three patriarchs were refined through the experience of some degree of exile. Jacob together with his sons, of course, descended into exile in Egypt, where they were in real exile, having had to leave their homeland. Jacob actually should have been brought to Egypt in chains, as our sages state in Shabbat 89b. The 400-year exile started with the birth of Isaac, though Isaac did not actually leave the Holy Land. He is however, always referred to as being גר, a stranger, in that land. Even though the patriarchs were not physically enslaved, the status of being sojourners sufficed to consider them as being in exile. Even Abraham, who was looked up to as a prince among the local population, and who had been "crowned" king in the עמק השוה, as we have mentioned earlier, suffered thirty years of mental exile during the years between the ברית בין הבתרים and the birth of Isaac. Jacob was especially pursued by the קליפה, for Samael had managed to injure Jacob's ירך, thigh, hip joint. As a result, Jacob was in need of greater refinement than his father or grandfather, which manifested itself in a more serious form of exile. Although Esau was a son of Isaac, and honored his father, [which indicated Isaac's affinity to that קליפה of his, Ed.], the fact that Esau lived a life designed to lead to physical as well as spiritual death (as we know from his own admission in Genesis 25,32 when he sold the birthright, and again when he wished for his father to die prematurely, Genesis 27,41) meant that Isaac had rid himself of that קליפה and therefore only needed a minimal amount of exile experience. Abraham died before Esau had become wicked, and thus had no affinity to Esau's קליפה. Abraham also expelled Ishmael from his home when G–d commanded him to pay heed to what his wife Sarah had told him, namely to expel the servant woman and her son. As a result of his keeping away from both these קליפות Abraham did not have to experience actual exile. He did not even have to feel as a stranger. All that was needed to refine him was the anxiety experienced between the promise of the birth of an heir and the fulfillment of that promise, which meant the onset of the 400 years of his descendants being regarded as strangers or of their being actual slaves.