As a result of the late birth, Yaśodharā needed to prove that Rāhula was really Prince Siddhārtha's son, which she eventually did successfully by an act of truth.

The Pāli account claims that when he received the news of his son's birth he replied "rāhulajāto bandhanaṃ jātaṃ", meaning "A rāhu is born, a fetter has arisen",[14][13] that is, an impediment to the search for enlightenment.

Accordingly, Śuddhodana, Prince Siddhārtha's father and king of the Śākya clan, named the child Rāhula,[13] because he did not want his son to pursue a spiritual life as a mendicant.

[17][18] The Mūlasarvāstivāda tradition relates, however, that Rāhula was conceived on the evening of the renunciation of Prince Siddhārtha, and born six years later, on the day that his father achieved enlightenment,[9] which was during a lunar eclipse.

[note 2] The king refused to issue a punishment for such a trivial matter, but had his brother wait for his final decision and constrained in the royal gardens.

After six days, the king suddenly realized he had forgotten about the hermit and immediately set him free, including apologies and gifts.

However, in the 13th-century Japanese devotional text Raun Kōshiki, Rāhula's late birth is seen as evidence of a miracle, rather than a result of karma.

[28][29][note 3] The second type of explanation consists of the more naturalistic argument that Yaśodharā was practicing religious austerities involving fasting and sleeping on a straw bed, which caused Rāhula's growth to slow down.

Buddhist Studies scholar John S. Strong notes that this account draws a parallel between the quest for enlightenment and Yaśodharā's path to being a mother, and eventually, they both are accomplished at the same time.

[33] Furthermore, in both the Mūlasarvāstivāda texts and the Mahāprajñāpāramitāupadeśa, there is a third account that proves Yaśodharā's purity in conduct: in this version, the Buddha made everyone around him look identical to him, through a supernatural accomplishment.

[32][34][note 4] In a fourth story about proving Yaśodhara's purity, appearing in Chinese Avadāna-style texts from the 5th century CE onward, she was burnt alive, but miraculously survived.

[36] Religion scholar Reiko Ohnuma sees the fire ordeal as a metaphor that parallels the Buddha's enlightenment, a similar argument that Strong makes.

Orientalist Noël Péri believed, however, that a late gestation period was more historically probable than the birth on the same day, as in the Pāli tradition.

[41] Buddhist studies scholar John S. Strong hypothesizes that the Mūlasarvāstivāda version of the story of the prince conceiving a child on the eve of his departure was developed to prove that the Buddha was not physically disabled in some way.

[13] The Mahāvastu text from the Lokottaravāda tradition states that the royals tried to prevent Rāhula from learning about the return of his father, but eventually he insisted to know who the "Great Ascetic" about to arrive was, and he was told.

Let us take refuge in and pay highest homage to Venerable Rāhula, who was born and went forth in order to benefit sentient beings."

Rāhula was ordained, becoming the first śrāmaṇera (novice monk),[9] and probably the first person in the monastic order to receive ordination in a formal way.

[52][53] The king discovered that his grandson, his son Nanda and a number of other young men in the royal family had then received ordination and left the palace.

[17][13] In this discourse, the Buddha taught and encouraged consistent self-reflection, to help let go of all evil actions that lead to harm to oneself and others, and to develop self-control and a moral life.

[65][67] On a similar note, the Buddha taught Rāhula at a place called Andhavana about the impermanence of all things, and instructed him how to overcome the "taints" inside the mind.

E.g. after there was a rule established that no novice could sleep in the same room as a fully ordained monk, Rāhula was said to have slept in an outdoor toilet.

[17] Schumann writes that the Buddha's relationship with his son was "... trusting and friendly, but not cordial or intimate", in order to prevent attachment in the monastic life.

Tradition states therefore that Rāhula will be alive until the next Buddha, and until that time resides with 1,100 of his pupils in an island called the 'land of chestnuts and grains' (Chinese: 畢利颺瞿洲; pinyin: Biliyangqu zhou).

[79] The pilgrim Xuan Zang (c.602–664) heard a brahmin claim that he met Rāhula as an old man, who had delayed his passing into Nirvana and was therefore still alive.

[85] The Chinese monks Xuan Zang and Faxian (c.320–420 CE) noted during their pilgrimages in India that a cult existed that worshiped Rāhula, especially in the Madhura area.

[86] The two Chinese pilgrims noted that Emperor Aśoka built a monument in honor of Rāhula, especially meant for novices to pay their respects.

[17] Religious studies scholar Lori Meeks points out with regard to Japan, however, that Rāhula was not the individual object of any devotional cult, but was rather honored as part of a group of enlightened disciples, such as the 16 Elders.

On regular days of religious observance, male and female novices performed rites and gave lectures in honor of Rāhula.

[98][99] Religion scholar Vanessa Sasson notes that although Prince Siddhārtha initially abandons his son, he comes back for him and offers a spiritual heritage to him as opposed to a material one.

[100] The acceptance of Rāhula in the monastic order as a child set a precedent, which later developed into a widespread Buddhist tradition of educating children in monasteries.