One of this week's two Parshiyos, Bechukosai, is highlighted by the famous Tochachah, the rebuke. It is therefore a very difficult and painful Parsha, foretelling the curses and suffering which the Jewish people will endure due to their sins. But at the same time, the Tochachah carries a message of hope. There is a promise that Hashem will remember His covenant with the Avos (ויקרא כ"ו:מ"ב) and therefore He who carries out the punishments listed in the Tochachah will also carry out the vision of redemption and will fulfill His promises of good to the Jewish nation. Therefore, the Tochachah predicts tragic episodes full of misery, but ones which will end up to the ultimate redemption.
The Meforshim explain in our Parsha that there is a purpose to our Golus, our exile, and the suffering that we have undergone as a result of it. We say in davening on Yom Tov and Rosh Chodesh, "ומפני חטאנו גלינו מארצנו," "because of our sins we were exiled from our land." But although the exile is a punishment, according to Chazal, our dispersion among the nations has been a blessing in the midst of a curse, because throughout this Galus, the nations of the world were unable to destroy us. Our experiences have, in fact, strengthened us as a nation. Even though we had to wander from one place to another, we always kept a central focus, from which the Jewish spirit could grow again and again. This wandering is thus understood by the commentators as being good, and having a positive aim. By having to wander, we would not become assimilated among the nations as a result of becoming too deeply rooted in a single place; we would be able to maintain that Jewish focus.
The Chasam Sofer notes the extraordinary phenomenon that the more Israel tries to draw closer to the other nations, the more the hatred of the nations increases. This theory has been tried and tested. He then explains, that the other nations of the world will attempt to destroy the Jews physically, but this too will ultimately have a good effect, because as a result of being persecuted, our Judaism will stand out and this will preserve the existence of the Jewish people.
The Meshech Chochmah expands on this, analyzing Jewish history in light of one outstanding fact. From the of Yaaakov Avinu, the Jews have been a foreign and separated nation among the other nations of the world. They have always erected various barriers between them and the other nations in order to keep themselves separated from them. When this condition exists all is well with gentile neighbors. It is only when the Jews believe that because they are living among others, they should attempt to become part of them that they become as thorns in the sides of the other nations. An outside storm then uproots them from their place, which seemed to them to be secure, and once again they are thrown among strangers whose language they can not speak. Once again, though, find it impossible to assimilate.
According to the Meshech Chochmah, then, this forced move decreed by Hashem has a certain "national" value to us, in that it prevents total assimilation. When the Jews finally become too comfortable in their new country, and when all is calm and the Jews once again begin to assimilate, the forced move forces us to return to our original sources and independence. The purpose of our wandering, then, is to undermine our imaginary security, and to instill in us the recognition that it is our duty to fortify ourselves with our spiritual treasures, and not to seek new ways which our ancestors did not know.
The Ba'al Akeidah, too explains the Galus along these same lines. He interprets the Posuk in Devarim (כ"ח:ס"ה) which says that when in exile among these nations we shall find no ease, as both a promise and a warning. Any attempt to assimilate among the other nations will not be successful, for Hashem will differentiate and not separate us from the other nations. He will cause hatred towards us, and even decree annihilation upon you. There is no fleeing our destiny as Jews. Similarly, the Ba'al Akeidah interprets the curse that we shall be sold there to our enemies as slaves but that no one will buy us (שם פסוק ס"ח) as a blessing as well. Almost never in all of our history have we been sold into slavery, as many other peoples have. Instead, we have been subject at times to the good graces of various kings, and their desires, which were controlled by Hashem. The same is true for many other curses in the Tochachah. They are indeed curses, but with hidden blessings, and although each may seem originally to be only a curse, it is later shown that each is truly a blessing.