Jaina or Buddhist
Ajatasatru enjoys a respectable position in both Jaina and Buddhist traditions. Both claim him as a close follower, and both come forward with evidence in support of this claim. According to Buddhist tradition, the Samaññaphala Sutta deals with his first meeting with the Buddha. According to the same text, during this meeting, Ajatasatru took protection of the Buddha, the Dhamma and the Sangha. This Sutta records his devotion towards the Dhamma. He erected a vast Stupa on the bones and ashes of the Buddha after the funeral, and Ajatasatru also was present in the first Buddhist council at the Sattapanni (Saptparni) caves Rajgriha.
On the other hand Uvavai/Aupapātika sutta, which is the first Upānga (see Jain Agamas) of the Jains throws light on the relation between Mahavira and Ajatasatru. It accounts that Ajatasatru held Mahavira in the highest esteem. The same text also states that Ajatasatru had an officer to report to him about the daily routine of Mahavira. He was paid lavishly. The officer had a vast network and supporting field staff through whom he collected all the information about Mahavira and reported to the king. The uvavai Sutta has detailed and illuminating discussion on Mahavira's arrival at the city of Champa, the honour shown to him by Ajatasatru, the sermon given by Mahavira in Ardhamagadhi language, etc..
If the Samaññaphala Sutta and Uvavai Sutta are placed side by side, then the Uvavai Sutta will appear to be more profound in depth and penetration. The only line in the Samaññaphala Sutta that would give support to Ajatasatru's having become a Buddhist is: "From this day Bhagavān please accept me as thy follower, I seek your protection with folded hands." In contrast, the Uvavai has a more detailed account: The officer in charge of Mahavira's routine, Ajatasatru coming down the throne expressing his feelings and obeisance with utterance of the word Namothhanam, his meeting with Mahavira and his concluding words, "What to speak of the excelling thee, none other Sramana or Brahmana could have given such a brilliant exposition of the Dhamma as thou hast done." Also, Ajatasatru was present in the first council under the guidance of Sudharma swami, the spiritual successor of Mahavira.
Indologist Vincent Arthur Smith has written "Both traditions have claimed him as one of themselves. The Jaina claim appears to be well founded. Whereas Ajatasatru met Buddha only once, he had several meetings with Mahavira. Buddha spent only 5 monsoon camps in Rajgriha and none in Champa, Ajatasatru's capital, while Mahavira spent 14 monsoon camps in Rajgriha and 3 in Champa. " According to another Indologist, Radha Kumud Mookerjee, "So long as both Mahavira and Buddha were alive, Ajatasatru was a follower of Mahavira. Other evidences that suggests that he could not have been a Buddhist, viz., His intimacy with Devadatta, who happened to be enemy of the Buddha.". Aacharya Sri Nagrajji, D.Litt. in Comparative studies of Jainism and Buddhism, says "For the victory from Vajjis, Ajatasatru sent his minister Vassakara to the Buddha. This was a conspiracy to know the secrets of Vajjis from the Buddha. If he would be a true follower of the Buddha, how would he have played such a mean trick with him?" He further says, "It is written in Atthakathas that Ajatasatru butchered 500 Nirgrantha monks after murder of Moggallana. This seems to be no more than a fiction, as had it been true, the Jainas wouldn't have held Ajatasatru with great respect." Finally, Thomas William Rhys Davids a pāli and Buddhist scholar has written, "There is not a single proof in the Tripitakas stating that Ajatasatru ever became follower of the Buddha. So far as I have been able to understand, after he met Buddha once, he never again met the Buddha or any other monk of the Buddhist order, neither did he discuss about the religion with any of them; and nor did he make any financial donation to the Buddhist order in life-time of the Buddha." He further says "Of course, this is much known that he sent a request of share of the bones and ashes of the Buddha; but his justification for this request was that "I am a kshatriya and so was the Buddha" and then he erected an altar on the bones. Later it is recorded that immediately after the Buddha's death, the Buddhist Council met. Ajatasatru had erected a huge conference hall near the entrance of Saptparni cave, where the Buddhist Pitikas were compiled. But the older Buddhist texts are silent on this. Therefore, it is very likely that even without courting the religion of Buddha, he had a great regard for this religion. In doing so, Ajatasatru was only following the great tradition of Kingship of India, according to which it was the sacred duty of a ruler to extend protection to all religions. But as far as the religion which Ajatasatru followed is concerned, it has to be Jaina by all evidence." Thus, by all the above evidence and comments of the historians, it is clear that Ajatasatru was a devout follower of the Jaina religion as preached by Mahavira.
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