A teaching of Menahem Mendel of Kotzk, given over by Yehuda Leib Alter of Ger, from Sfas Emes, Parshat Mishpatim.
You shall be a holy people unto Me. Do not eat of any meat [of an animal] left torn in the field. Exodus 22:30
A teaching in the name of the holy rabbi [Menahem Mendel] of Kotzk: “You shall be a holy people” teaches us that holiness must be pursued within our own human lives and worldly affairs (1). For God has no shortage of heavenly angels, ministers of fire and holy creatures, but God’s desire is for a human holiness; that is why He put sparks of holiness in this finite, material world. Of this we learn from the verse Do not eat of any meat [of an animal] left torn in the field, to which the sages added, “This teaches the general principal that everything that breaks its [natural] boundaries is forbidden” (2). For everything has its own measure of holiness, and we must keep check on our materiality so that it does not cross over into the realm of the holy. You shall be to me a holy people is also a promise, that in the end Israel shall be holy to God.
1) The Sfas Emes’ grandfather, Yitzhak Meir of Ger, was a fellow-disciple with the Kotzker of Simcha Bunam of Peshischa, and he accepted the Kotzker as his teacher after Simcha Bunam’s death. Yitzhak Meir would take his grandson, Yehuda Leib, to visit the Kotzker until the rebbe’s death, when the Sfas Emes was twelve. 2) Zevachim 82b
The Kotzker was known for being radical in his demands on his disciples, so you might expect him to call for a withdrawal from ordinary life to one given over entirely to study and mitzvot. On the contrary, the Kotzker saw this as the easy way out and took what he saw as the more radical and demanding path of staying in the world, and bringing into it as much holiness as we can, day in, day out.