What does the dog represent in Hindu mythology that renders it inauspicious?
In Hindu mythology, the dog is the most inauspicious animal, to be kept away from wedding altars and holy sites. A howling dog becomes a harbinger of bad luck. In fact, even the sight of a dog is considered to bring bad luck. [An example of this is Janamejaya's Sarp Yagya in which his sons tried to push one dog away from the Yagya site.]
Why is it so? Dogs are such lovable creatures, obedient and affectionate. Even in the Rig Veda, the role of a dog as a protector, is acknowledged when Indra sends the mother of dogs, Saramaa, in search for missing cows.
In narratives, dogs are associated with death which is why Saramaa's children, the Sarameya, are the companions of Yam, god of death. They are associated not with civilization but with the wilderness which is why they are associated with mendicants, like Dattaatreya. The dog is the mount of Bhairav, the fearsome form of Shiv. A dog is considered so inauspicious that in Mahaabhaarat, Yudhishthir is not allowed to enter heaven with the dog. On the other hand to test Yudhidhthir, Dharm Raaj assumed only the form of a dog.
Some would argue that dogs rummage through garbage which is why they are unclean, which is why they are not allowed to come near temples. But these rational explanations do not provide a satisfactory answer. Literal interpretations are convenient but not correct. Logically speaking, a dog should be the symbol of devotion in Hinduism; yet Hindu worship Hanumaan, the monkey-god, as the perfect devotee. Mythology must never be taken literally; mythology is symbolic. Mythic stories and symbols are a code, a medium through which the ancestors are communicating profound messages. When the dog is considered inauspicious, it means the dog represents a thought that is inauspicious. What is this inauspicious thought?
In Bhaagvat Puraan is the story of Bharat who is a hermit in the forest. He gives up everything but slowly gets attached to a deer. As a result, he is unable to attain Moksh. He is reborn as a deer, trapped once more in the cycle of rebirth. Attachment entraps: This is a key maxim of Hindu philosophy.
Now visualize a dog looking at you with eagerness and affection it adores you and its behavior melts your heart. If you have a pet dog, you will know the dog constantly seeks validation from you. Give it that attention it craves and it will wag its tail, don't give it and it will whine.
Now visualize a hermit surrounded by dogs. Does he surrender to the affection of the dog? Does he, like Bharat getting attached to a deer, get attached to these dogs? If he seeks to break free from the cycle of rebirths, he must transcend the urge to get attached. The dog is the ultimate temptation, because the dog gives its master absolute unconditional love and devotion. Nothing is more tempting, not even the dance of damsels known as Apsaraa. When Dattaatreya, the mendicant, walks with four dogs around him, it indicates his perfect detachment. The dogs follow him but he does not lead them.
The dog is a territorial animal. For the dog, even the master is territory that it will not share. Even when domesticated with all needs fulfilled, the dog needs to mark its territory by raising its legs and spraying its urine. Threaten this territory and the dog will turn on you. This behavior, the ancients realized, is not something to be celebrated in human beings.
Human beings are also territorial. Territory gives us our sense of identity and validation. It is the context that establishes who we are. An industrialist's identity comes form the industries he owns; a bureaucrat's identity comes from the position he holds; a politician's identity comes from the power he holds in the party and the assembly. Any threat to the context that gives him identity, and he will react much in the same way a dog barks.
We feel that if we lose our territory (not just physical but also intellectual and emotional), we will lose our identity. That frightens us. We become dogs wagging tails when territory is reinforced, barking when territory is threatened, whining when territory is unacknowledged. At the root of this dog-like behavior is fear, Bhaya, fear of invalidation.
He who helps us overpower this fear is Bhairav. This form of Shiv terrifies us because it mocks our primal territorial instinct. In temples such as Kaal Bhairav in Delhi and Vaaraanasee, Bhairav is worshipped with alcohol. Alcohol clouds judgment. From a clouded judgment comes this warped understanding that from territory comes identity. The industrialist forgets that even if he clings and fights for his territory, one day Yam, the god of death, and his Sarameya, will take his away from his territory. So it will be with the politician and the bureaucrat and the writer and the artist.
Our material, intellectual and emotional territories that we jealously guard, whose loss makes us insecure, are no different from the bone of a dog. We cling and fight over it, until the day we die. And when we die and our bodies reach the crematorium, we find there an inebriated Bhairav seated on a dog laughing at us for a life wasted in a futile pursuit.
(1) Dog in Ved
(4) Rig Ved Rishi have mentioned Dogs in at least 3-4 Mantra in Rig Ved, however, the given story by old wise man is perhaps not in Upanishad. Upanishad doesn't contain text related to popular Indra - Sinhaasan and Devtaa and Daitya, God or Demon type stories, their subject is only Brahm and Aatmaa.
(2) Indra's Dog
--Indra himself has a bitch named Saramaa whose son was abused by Janamejaya's brothers when he was doing Sarp Yagya. At that Saramaa cursed Janamejaya that his Yagya will come to stop in between by a Rishi. (Mahabhaarat, MBH, G-0/4)
--Saramaa is said to have pursued and recovered the cows stolen by the Panai Asur and hidden in the nether world of Paataal.
(3) Yam Raaj's Dog
Yam Raaj, the God of death is believed to have two ferocious dogs Sarameyas (described as the off springs of Indra's dog). Both of these dogs have four eyes each and they guard the road to Yam Lok. Yam himself took the form of a dog, while guiding Yudhishthir to Swarg Lok, see below. [MBH, G-7/34]
(3) Kaal Bhairav's Dog
The vehicle of Kaalbhairav is a dog.
(4) Bhagavaan Dattaatreya's Dogs
Dattaatreya's picture can always be seen with four dogs following him.
(5) Yudhishthir's Dog
Yudhishthir had a dog with him when he was going to Swarg (in Swargaarohan Parv of Mahaabhaarat). He did not leave this dog in spite of Indra's threat that he would not be able to go to Swarg because the dogs were allowed in Swarg. In reality that dog was the father of Yudhishthir - Dharm Raaj himself, although he did not now it. [MBH, G-7/34]
Dog's Reference Elsewhere
Five Characteristics of a Student
Kaak cheshtaa, bako dhyaanam, shwaan nidraa, alpahaaree, griha Tyaagee,
......vidyaarthee panch lakshanam"
Roughly translated - the five indications of a good student are ---
(1) perseverance of a crow,
(2) concentration of a crane,
(3) light sleeper like a dog,
(4) light eater,
(5) staying away from home (means noise, emotions).