The Mishnah taught that one would bring the High Priest the goat to be slaughtered, he would kill it, receive its blood in a basin, enter again the Sanctuary, and would sprinkle once upwards and seven times downwards. He would count: "one," "one and one," "one and two," and so on. Then he would go out and place the vessel on the second golden stand in the sanctuary.Mishnah Yoma 5:4, in, e.g., The Mishnah: A New Translation, translated by Jacob Neusner, page 273. Babylonian Talmud Yoma 53b, in, e.g., Koren Talmud Bavli: Yoma, commentary by Adin Even-Israel (Steinsaltz), volume 9, page 261.
