Thus have I heard:
One time, the Budha was staying at Anaathapindidas Ashrama in Jetavana of Shraavastii.
At that time, Bhagavaan said to the Bhikshus, “In this assembly, I do not see a single practice that, when cultivated and frequently practiced, leads to rebirth in hell, as an animal, or as a hungry ghost. If one is reborn as a human, their life will be extremely short.
What is this practice? It is killing. Bhikshus, if someone has a mind inclined towards killing, they will fall into hell, become a hungry ghost, or be reborn as an animal. If they are reborn as a human, their life will be extremely short. Why is this? Because they have taken the lives of others. Therefore, you should learn to abstain from killing.
Thus, Bhikshus, you should train yourselves in this way.”
When the bhikshus heard what the Budha said, they followed it with joy.