THE TWO DOGS OF YAMA EXPLAIN THEMSELVES.
There are not many things in heaven that can be represented as a pair, coursing across the sky, looking down upon the sea, and having other related properties. My readers will make a shrewd guess, but I prefer to let the texts themselves unfold the transparent mystery. The Veda of the Katha school (xxxvii. 14) says: "These two dogs of Yama, verily, are day and night," and the Brāhmana of the Kāushītakins (ii. 9) argues in Talmudic strain: "At eve, when the sun has gone down, before darkness has set in, one should sacrifice the agnihotra-sacrifice; in the morning before sunrise, when darkness is dispelled, at that time, one should sacrifice the agnihotra-sacrifice; at that time the gods arrive. Therefore (the two dogs of Yama) Çyāma and Çabala (the dark and the spotted) tear to pieces the agnihotra of him that sacrifices otherwise. Çabala is the day; Çyāma is the night. He who sacrifices in the night, his agnihotra Çyāma tears asunder; he who sacrifices in broad daylight, his agnihotra Çabala tears asunder." Even more drily the two dogs of Yama are correlated with the time-markers of heaven in a passage of the Tāittirīya-Veda (v. 7. 19); here sundry parts of the sacrificial horse are assigned to four cosmic phenomena in the following order: 1. Sun and moon. 2. Çyāma and Çabala (the two dogs of Yama). 3. Dawn. 4. Evening twilight. So that the dogs of Yama are sandwiched in between sun and moon on the one side, dawn and evening twilight on the other. Obviously they are here, either as a special designation of day and night, or their physical equivalents, sun and moon. And now the Çatapatha-Brāhmana says explicitly: "The moon verily is the divine dog; he looks down upon the cattle of the sacrificer." And again a passage in the Kashmir version of the Atharva-Veda says: "The four-eyed dog (the moon) surveys by night the sphere of the night."