the Israelites to use the bunch of hyssop to strike the lintel and the two side-posts with blood in Noting that the cedar was among the tallest of tall trees and the hyssop was among the lowest of low plants, the Midrash associated the cedar with arrogance and the hyssop with humility. The Midrash noted that many things appear lowly, but God commanded many precepts to be performed with them. The hyssop, for instance, appears to be of no worth to people, yet its power is great in the eyes of God, who put it on a level with cedar in the purification of the leper in and the burning of the Red Cow in 18, and employed it in the Exodus from Egypt in Rabbi Isaac noted two red threads, one in connection with the Red Cow in and the other in connection with the scapegoat in the Yom Kippur service of (which Mishnah Yoma 4:2 indicates was marked with a red thread). Rabbi Isaac had heard that one required a definite size, while the other did not, but he did not know which was which. Rav Joseph reasoned that because (as Mishnah Yoma 6:6 explains) the red thread of the scapegoat was divided, that thread required a definite size, whereas that of the Red Cow, which did not need to be divided, did not require a definite size. Rami bar Hama objected that the thread of the Red Cow required a certain weight (to be cast into the flames, as described in ). Rava said that the matter of this weight was disputed by Tannaim (as explained below). Abaye objected (based on Mishnah Parah 3:11) that they wrapped the red thread together with the cedar wood and hyssop. Rav Hanin said in the name of Rav that if the cedar wood and the red thread were merely caught by the flame, they were used validly. They objected to Rav Hanin based on a Baraita which taught that if the thread caught fire in midair, they brought another thread to prepare the water of lustration. Abaye reconciled the two opinions by interpreting the Baraita to speak of a flame that blazed high above the cow, and interpreting Rav Hanin to speak of a subdued flame that consumed the thread near the burning cow. Rava explained the dispute among Tannaim about the weight of the red thread in connection with