If in a book of the law the writing is obliterated all but eighty-five letters--as, for instance, in Num. x. 35, 36, "And it came to pass when the ark set forward," etc.,-- it may be rescued on the Sabbath from a fire, but not otherwise. Shabbath, fol. 116, col. 1.
Elijah said to Rabbi Judah the brother of Rav Salla the Pious, "The world will not last less than eighty-five jubilees, and in the last jubilee the son of David will come." Sanhedrin, fol. 97, col. 2.