- Throwing a large rock at him. Devadatta missed, but a splinter from the rock drew blood from The Buddha's foot.
- Inciting an elephant to charge at The Buddha. The Buddha was able to pacify the elephant by directing Mettā to it.
According to Sutta Pitaka, after trying to kill Sakyamuni a number of times, Devadatta set up his own Buddhist monastic order by splitting the (Sangha). During his efforts to become the leader of his own Sangha, he proposed five extra-strict rules for Monks, which he knew Buddha would not allow. Devadatta's reasoning was that after he had proposed those rules and Buddha had not allowed them, Devadatta could claim that he did follow and practice these five rules, making him a better and more pure Monk. One of these five extra rules required Monks to be vegetarian. In the Contemplation Sutra, Devadatta is said to have convinced Prince Ajatasattu to murder his father King Bimbisara and ascend the throne. Ajatasattu follows the advice, and this action prevents him from attaining enlightenment at a later time, when listening to some teaching of Buddha. Devadatta is the only individual from the early Buddhist tradition to have committed three anantarika-karmas.
King Suppabuddha was the father of Devadatta and Yasodharā and the father-in-law of Prince Siddhattha. One day Suppabuddha blocked The Buddha's path, he refused to make way, and sent a message saying, 'I cannot give way to The Buddha, who is so much younger than I.' Finding the road blocked, The Buddha and the Bhikkhus turned back. As The Buddha turned back, he said to Ananda, 'Because the king has refused to give way to a Buddha, he has committed a bad Kamma and before long he will have to face the consequences.' It is said that the king died on the seventh day after that event had taken place. He fell down the stairs, collapsed and died and was born in a Suffering state, being unable to escape the effects of his Evil Kamma (according to buddhist belief). According to The Buddha's prediction the earth swallowed him. It is said, "So the king went down the stairs and as soon as he stepped on the earth, it opened and swallowed him up and dragged him right down to Avici Niraya.".
Accounts claim that towards the end of Devadatta's Life, he was struck by a severe remorse caused by his past misdeeds and did indeed manage to approach The Buddha and retook Refuge in the Triple Gem, dying shortly afterwards. Because of gravity of his sins, he was condemned to suffer for several hundred millennia in Avici. However, it was also said that he would eventually be admitted into the heavens as a Pratyekabuddha due to his past merits prior to his corruption.
In the Samaññaphala Sutta, Gautama Buddha said that if Ajatasattu hadn't killed his father, he would have attained sotapannahood, a degree of enlightenment. But because he had killed his father he could not attain it.
In the Contemplation Sutra, Lord Buddha taught Ajatasattu's mother, Queen Vaidehi, those who attain birth on the lowest level of the lowest grade are the Sentient beings who commit such evils as the five gravest offenses, the ten Evil acts and all kinds of immorality, when he is about to die, he may meet a good teacher, who consoles him in various ways, teaching him the wonderful Dharma and urging him to be mindful of The Buddha; but he is too tormented by pain to do so, The good teacher then advises him say Namo Amitabhaya Buddhaya ten times. Because he calls The Buddha's Name, with each repetition, the Evil Karma which he has committed during eighty kotis of kalpas of Samsara is extinguished. When he comes to die, he sees before him a golden Lotus-flower like the disk of the sun, and in an instant he is born within a Lotus-bud in the Land of Utmost Bliss.