The Bad Ending of Greed

In the pre-Islamic era, two brothers set out on a journey and stopped to catch their breath in the shade of a tree on the side of the road. There was a stone under this tree. When they decided to walk after a while, a snake came out from under this stone carrying a dinar and placed it in front of one of the two brothers.
After finding this dinar, the two brothers said to each other, "What if there is a treasure buried here?" So they stayed there for three days and the snake brought one dinar every day and placed it in front of them. But on the fourth day, one of the brothers said:
"Brother! How long will we continue to earn one dinar each while sitting here? Why not kill this snake and take out the treasure?"
But the other brother forbade him and said:

"If the treasure is not found under it, then all our hard work will be in vain."
 But he did not listen to him and took an axe and sat down to wait for the snake. As soon as the snake pulled its head out of the stone, he struck it with the axe. But the attack was not entirely successful, and the snake was only injured, not killed. The snake quickly turned around and attacked back, biting and killing the attacker with the axe, then crawled back into the stone.
The other brother buried his dead brother and remained there. Until the next day, the snake came out again, but there was no dinar in its mouth and its head was tied with a bandage.  The snake came out and started towards him, but he immediately said:
"You know that I had forbidden my brother from doing this, and I did not agree with him in killing you, but this unfortunate man did not listen to me and attacked you, as a result of which he had to lose his life. Under these circumstances, is it not possible that you should not harm me and I should not harm you? And that you should be kind to me as you were kind to us for four days?"
But the snake answered him in the negative. The man asked:
"What is the reason for your refusal?"
 The snake replied:
"The reason for the denial is that I know very well that your heart will never be pure towards me, because I killed your brother and you are looking at his grave with your own eyes. And my heart cannot be pure towards you either, because this wound on my head will always remind me of the trauma that I had to endure at the hands of your brother."
Then the snake, who was originally a jinn, recited this poem by the genius Jadi:
"And I did not see any good dealings with my ally, although my wealth was nurturing him and was aware of his appearance."