Bava Metzia 114 - Prophet Elijah and Rabba Bar Avuha
Rabba Bar Avuha found Elijah the prophet standing in a cemetery of idolaters and asked him, "Why is master who is a Kohen standing in a cemetery?"
Elijah answered, "Did you not learn the Order of Purities?" For Rabbi Shimon Bar Yochai said, based on " Now you my sheep, the sheep of my pasture, are you called man ..." - about whom it is said, "... when a man dies in a tent ..." and therefore only Jewish graves are impure for a Kohen.
He said to Elijah, "I am not able to properly study the four most important orders, am I to study the sixth (Purities)? - for I am very poor."
Elijah brought him up to the Garden of Eden and told him to collect some leaves. Rabbah understood that he was spending his reward in the World To Come and threw the leaves away. Still, his cloak absorbed the smell, and he sold it for 12,000 golden dinars - and distributed them to his sons-in-law.