In everything that G-d taught Moses, He would tell him both the manner of contamination and the manner of purification. When G-d came to the laws concerning one who comes in contact with a dead body, Moses said to Him: "Master of the universe! If one is thus contaminated, how may he be purified?" G-d did not answer him. At that moment, the face of Moses turned pale. When G-d came to the section of the Red Heifer, He said to Moses: "This is its manner of purification."...