Before detailing the list of forbidden relationships the Torah instructs us: “Do not perform the practices of the land of Egypt in which you dwelled; and do not perform the practices of the land of Canaan to which I bring you..” Rashi writes that Mitzrayim and Canaan were the most morally decadent nations and in particular those parts in which the Jews dwelled were the worst sections of these countries. Why did Hashem deliberately place the Jewish people in the most corrupt places on Earth?
Rav Dessler zt”l answers this question in an essay in which he discusses how one should react to negative surroundings. He observes that negative society can have a very detrimental effect on a person. However, if he is strong enough so that the negative influences do not effect him, then, it can actually strengthen him in his Avoda. How is this so? Rav Dessler explains that when he sees the surrounding evil it becomes more disgusting in his eyes because he attains a greater recognition of its chesronos, this enables him to strengthen himself even further in his appreciation of good. Based on this understanding of human nature, Rav Dessler makes a historical observation that can explain why Hashem deliberately placed the Jewish people in the most degenerate places on Earth.
“Every time where there was a necessity for a tzaddik to rise to an extremely high level the tzaddik was flung into the most lowly and degenerate environments so that he could learn from them the lowliness of evil and strengthen himself in good to the opposite extreme.”
Hashem deliberately placed the Jewish people in Mitzrayim so that they could develop an intense hatred of its tuma which, he writes, was indeed their motivation for crying out to Hashem to free them from this terrible place. This intense disgust enabled them to rapidly rise from being on the 49th level of tuma to reaching the level of being able to receive the Torah. Had they found themselves in a less immoral environment then they would not have been able to rise to such a high level.
This too would seem to explain why the Jewish people had to go to a similarly abhorrent land. Seeing the highly immoral behavior of the Canaanite nations was intended to intensify their disgust at evil and in turn, heighten their appreciation of Torah morality.
Rav Dessler uses this yesod to help understand another passage discussed in the parsha - the Seir l’Azazel. On the most holy day of the year, Yom Kippur, Hashem commands us to take a goat through the desert and throw it off a cliff. What is the significance of leading the goat through the desert? Rav Dessler explains that the desert is the makom where people sacrifice goats to sheidim. By leading the goat through this tamei place and being exposed to its tuma on Yom Kippur, the people become further strengthened in Avodas Hashem.
Rav Dessler’s yesod also helps us understand some inyanim relating to Pesach. We begin the Haggadah discussing our ancestors who worshipped idols. Rav Dessler asks, how is this connected to the story of leaving Mitzrayim? He answers that through being surrounded by such negativity, Avraham Avinu rose to such a high level of kedusha to the extent that its power would never be nullified. The geula from Mitzrayim sprouted directly from this kedusha.. Therefore, we talk about our idol-worshipping ancestors to highlight that it was directly as a result of their tuma that Avraham emerged to reach such an incredibly high level and it was his greatness in turn that planted the seeds for yetsias Mitzrayim.
We can now gain a deeper understanding of why the Haggaddah goes to considerable length to discuss the negative influences that include our idol-worshipping ancestors, the Mitzrim and Lavan. Perhaps this is intended to arouse our disgust at such immoral people and in turn, heighten our appreciation of Hashem for freeing us from them and giving us the Torah.
In today’s world, the nisayon of secular influences is unavoidable. Even if we live in observant neighborhoods, the myriad negative influences bombard us daily. It is of course highly advisable to strive to reduce their influence as much as possible but nonetheless it is impossible to completely eliminate any exposure to them. Rav Dessler’s yesod can help us deal with these influences and perhaps even use them for the good. By observing the obvious chesronos of the secular world we can enhance our appreciation for the beauty of the Torah lifestyle. May we all merit to protect ourselves from negative influences and instead to use them to grow closer to Hashem.
 Acharei Mos, 18:3.
 Michtav M’Eliyahu, 1st Chelek, p.157-160
 Ibid. p.158.
 Of course, the Jewish people had bechira as to whether they chose to completely reject the ways of the Canaanim or to accept them as neighbors an thereby be influenced negatively. History shows that they did not completely destroy their neighbors and in time they came to be negatively influenced by the Canaanim.