A disciple of the wise who makes light of the washing of hands is contemptible; but more contemptible is he who begins to eat before his guest; more contemptible is that guest who invites another guest; and still more contemptible is he who begins to eat before a disciple of the wise; but contemptible before all these three put together is that guest which troubles another guest. _Derech Eretz Zuta_, chap. viii. A roll of the law which has two mistakes to a column should be corrected; but if there be three, it should be stowed away altogether. _Menachoth_, fol. 29, col. 2. The wolf, the lion, the bear, the leopard, the panther, the elephant, and the sea-cat, each bear three years. Ibid. Rav Yehudah says, in the name of Rav, "The butcher is bound to have three knives; one to slaughter with, one for cutting up the carcass, and one to cut away the suet. Suet being as unlawful for food as pork." _Chullin_, fol. 8, col. 2. Three classes of ministering angels raise a song of praise every day. One class says, Holy! the second responds, Holy! and the third continues, Holy is the Lord of hosts! But in the presence of the Holy One--blessed be He!--Israel is more beloved than the ministering angels; for Israel reiterates the song every hour, while the ministering angels repeat it only once a day, some say once a week, others once a month, others once a year, others once in seven years, others once in a jubilee, and others only once in eternity. Again, Israel mentions The Name after two words, as it is said (Deut. vi. 4), "Hear Israel, Yehovah," but the ministering angels do not mention The Name till after three, as it is written (Isa. vi. 3), "Holy! holy! holy! Yehovah Zebaoth." Moreover, the ministering angels do not take up the song above till Israel has started it below; for it is said (Job xxxviii. 7), "When the morning stars sang together, then all the sons of God shouted for joy." _Chullin_, fol. 91, col. 2.