Its not worshiped, but respected along with anything thats associated with Hindu Gods.
The culture of giving the animal "respect"
for the help it bring to rural household in medieval times has been transformed to a certain worship by a group of people.
An Indian cow is born , bred/fed/ , used and is killed/dead in the same process the same way if the cow is in Africa or in western Australia. I dont find anything godly in it.
There are several hundred breeds of cows in the world world .
Would you consider holstein friesian breed from North Holland as a god too?
The ideas/ ideologies of the past are passed on by the uneducated rural mass as part of theirr culture wich has been misinterpreted by even todays generation in the name of showing "see we are religious too".
Hinduism is not confined to making everything "Godly" as you like. Yes
Hinduism believes there is presence of God in every matters we see , touch and are around.
So IMO even a mosquito is as godly as a cow.
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You talk cow being worshipped on Mattu Pongal.
What happens to it in rest of the year?
Its made to sleep/sit/stay in the worst of the conditions in sheds, been made to grase under sun, tie it up in ropes, beat it to move it and what not?
Is it the way to treat a God? Or it gets godly status only on Mattu pOngal day?
Religion is getting manipulated by few, who has set their own rules as if they are following Taliban type ideology. Im sorry for the harsh words but its true.
Read my signature.
It says
From ignorance, lead me to truth;
From darkness, lead me to light;
From death, lead me to immortality