For I am Hashem your G-d. Sanctify yourselves therefore, and be holy; for I am holy. You shall not defile yourselves with any kind of creeping thing that moves on the earth: For I am Hashem who brought you up out of the land of Egypt, to be your G-d. You shall therefore be holy, for I am holy: For I am Hashem who brought you up out of the land of Egypt, to be your God. You shall therefore be holy, for I am holy.
Klal Yisroel is different to all other nations. Hashem never considered Himself the G-d of any other nation other than Klal Yisroel. We have been chosen in a way that no other nation was.
For this reason, we need to distance ourselves from any impurity.
This is the meaning of the possuk כִי אֲנִי ה' אֱלוקיכֶם - for I am Hashem, your G-d, I announced myself as your G-d, and therefore וְהִתְקַדִשְתֶם וִהְיִיתֶם קְדֹשִים – sanctify yourself and be holy. We need to live up to our spiritual level as Hashem’s nation.
The Ohr Hachaim continues to explain the pessukim here.
וְהִתְקַדִשְתֶם וִהְיִיתֶם קְדֹשִים - Sanctify yourselves therefore, and be holy. If we sanctify ourselves as much as we can, being careful not to allow anything disgusting to enter our bodies, we will end up being holy. Just like the Gemara tells us that Hashem does not allow anything untoward to happen to the animals of Tzadikim, He certainly will not allow something untoward to happen to the Tzadik himself. Tosfos explains that this concept was said regarding food consumption. Hashem does not allow forbidden food to be consumed by a Tzadik.
Another explanation offered by the Ohr Hachaim is that we should sanctify ourselves by adding protective legal fences, which are Rabbinic ordinances that are designed to reduce the likelihood of a person consuming forbidden items. If we do so, taking the utmost care ourselves not to consume something forbidden, Hashem will sanctify us and save us from any mistakes.
כִי קָדוֹש אָנִי - for I am holy. Hashem depended our holiness on our acceptance of these legal fences. If we accept these fences and keep far away from sin, Hashem will sanctify us too.
וְלֹא תְטַמְאוּ אֶת נַפְשֹתֵיכֶם - You shall not defile yourselves. The continuation of the possuk is a promise from Hashem that if we act as we should, Hashem will ensure that we never become defiled. Hashem will guard us from any aveira.
Another thing hinted at in these pessukim is that the enemies of Klal Yisroel, those who wish us bad and are likely to make us suffer, are likened to disgusting insects and parasites. If we are careful to sanctify ourselves as we should, Hashem will sanctify us and prevent the insects and parasites from having any power or influence over us.
The possuk then proves this point כִי אֲנִי ה' הַמַעֲלֶה אֶתְכֶם מֵאֶרֶץ מִצְרַיִם. Hashem will protect the Jewish people from becoming enmeshed in the sin of contamination by impurity. We see this from the fact that he took Klal Yisroel out of Mitzrayim, which was the epitome of a contaminated environment, and their souls were completely submerged in it.
If Klal Yisroel sustains itself through these abominations, eating foods that are contaminated with the prohibition against eating them, they will effectively be returning themselves to Mitzrayim.
If Klal Yisroel takes active steps to prevent themselves from falling into the abyss of forbidden foods, Hashem will attach them to Him, and He will act as He did in Mitzrayim, rescuing Klal Yisroel from the depravity of the evil side, and uplifting us as He did when we left Mitzrayim.
On a slightly different note, the Ohr Hachaim explains that Hashem did not wish to atttach His name to Klal Yisroel until they left Mitzrayim and its impurities. If they do not protect themselves from impure foods, they will not merit Hashem’s name being attached to them. The Torah is giving us a reason for Hashem’s conditioning His sanctifying us on our keeping away from forbidden foods. Just as Hashem removed us from Mitzrayim in order to attach us to him, so too do we have to be removed from impurity to be attached to Hashem.
