There lived a brahmin, Haridatta. He was a very poor farmer. One noon he fell asleep and dreamt of a big snake. It spread its hood and disappeared. Haridatta woke up. He thought that this snake should be the guardian angel of that place.

He decided to worship it daily. He daily carried milk in a mud vessel. He prayed "O serpent king - Gaurdian of this place! I worship thee! Please accept my little offering!" Then he used to pour the milk inside the hole and go away.
Next day he came carrying milk. He found a gold coin placed in the mud vessel left by him the previous day. He felt very happy. He then worshipped the serpent with the milk offering and went home.  Then he continued his worship daily. Every day he used to get a gold coin in the mud vessel. Several days passed....

One day Haridatta had to go to another village for some urgent work. He asked his son to worship the snake God with the milk. He gave his son a milk vessel.

The boy went to the field and started worshipping the snake. The snake came out, spread its hood and drank the milk. The boy also saw the snake placing a gold coin in the vessel.  The boy thought that "the snake-hole must contain lot of gold coins. If I can drive away the snake, I can get all the gold."

Next day he went with a milk vessel, placed before the snake hole and prayed. The snake came out to drink the milk. The boy hit the snake with a stick injuring it.  The snake hissed and bit him. The boy died immediately.

The neighbors took the body. It was cremated. When Haridatta came and learnt about the death, he wept bitterly crying "The snake had faith in me. The boy did evil to the snake. My son is to blame for this".

Next day Haridatta went to the field with milk and worshipped. The snake came out and told him "See the ashes of your son. Also see the wound on my head caused by him. We can no longer be friends. For you will always be having sorrow in your mind about your son's death. I also will be remembering the harm done to me by your son. Please do not come hereafter. Our friendship is broken for ever". So saying it threw a diamond and disappeared.

Moral of this story:
Friendship once broken by a hasty action can never be regained again.