And an earthen utensil, which one of these falls into its inside…
Leviticus 11:33
And G-d formed man of the dust of the earth, and He blew into his nostrils a spirit of life.
Genesis 2:7
The laws of tumah and taharah (ritual impurity and purity) differentiate between an earthen utensil and utensils made of other materials. All utensils become impure through the contact of an impure object (e.g. the carcass of an impure animal) with any part of the utensil. An earthen utensil, however, becomes impure only if the source of impurity enters into its inside.
Said Rabbi Menachem Mendel of Kotzk: The value of a utensil of wood or metal is not only in its form—the material of which it is made is also worth something. So contact with any part of it, including its outside surface, has an effect upon its ritual state. An earthen utensil, however, has value only as a container; so it is affected only by what happens to its inside.
Man is an earthen vessel. His worth lies not in his material exterior, but in its content. He should therefore regard as significant only what pertains to his inner self.
Adapted from the teachings of the Rebbe by Yanki Tauber