Parashat Hukkat opens with the ritual of the parah adumah, the red heifer.  When a person has had contact with the dead, they are considered impure—tamei meit.  This designated animal is burnt and its ashes are mixed with water which is then used to purify anyone who was affected by this impurity.  This ritual is considered to be one of the most mystifying of the Torah and one of the most challenging mitzvot to understand.  This is in large part because any person who is part of the process of producing these purifying waters themselves become impure, though the water itself is a purifying agent.  Why is this so? Solving this “mystery” of how a pure person becomes impure in the process of removing someone else’s impurity will teach us about what it means to truly invest in and sacrifice for someone else.  It will also encourage us to recognize and appreciate the invisible investments and sacrifices that we benefit from.