Olive What He’s Having
During the Second Temple period, Eretz Yisrael suffered from a great famine. The great sage Rebbe Yochanan HaChorani survived by subsisting on dried bread and salt. His student Rebbe Elazar bar Rebbe Tzadok, who was better off, was moved by the plight of his rebbe. He told of his rebbe’s dire circumstances to his father, Rebbe Tzadok, who was a sage in his own right. Rebbe Tzadok sent a gift of fresh olives with his son to bring to his rebbe. However, Rebbe Yochanan HaChorani noticed that the olives were moist with olive oil and refused to eat them.
Produce cannot become susceptible to tumah while still attached to the tree or ground. After harvesting, it becomes susceptible to tumah after coming into contact with any of seven particular liquids, one of which is olive oil. It does not actually become tamei, however, until the produce comes into contact with an actual source of tumah. Rebbe Yochanan HaChorani saw that the olives were moist and assumed that they were susceptible to tumah, and he suspected that they might have actually become tamei. He therefore refused to eat them. He thanked his student profusely but refused to accept the gift, with the explanation of, “I don’t eat olives.”