Tassa pañhākamme ayamanupubbikathā:- ayaṃpi hi padumuttarabuddhakāle haṃsavatiyaṃ kulagehe paṭisandhiṃ gahetvā aparabhāge satthu dhammadesanaṃ suṇanto satthāraṃ ekaṃ bhikkhuṃ tejodhātukusalānaṃ aggaṭṭhāne ṭhapentaṃ disvā adhikārakammaṃ katvā taṃ ṭhānantaraṃ paṭṭhesi. So yāvajīvaṃ kusalaṃ katvā devamanussesu saṃsaranto imasmiṃ buddhuppāde sāvatthiyaṃ brāhmaṇakule nibbatto, sāgatamāṇavotissa nāmaṃ akaṃsu. So aparabhāge satthu dhammadesanaṃ sutvā paṭiladdhasaddho pabbajitvā aṭṭha samāpattiyo nibbattetvā tattha vasībhāvaṃ pāpuṇi.

Athekadivasaṃ satthā cārikaṃ caramāno kosambiyanagarasamīpaṃ agamāsi. Tena ca samayena nadītitthe porāṇakanāvikassa bahū āgantukagamikā verino hutvā taṃ pothetvā mārayiṃsu. So viruddhena cittena paṭṭhanaṃ ṭhapetvā tasmiṃyeva titthe mahānubhāvo nāgarājā hutvā nibbatto. So viruddhacittattā akāleyeva vassaṃ vassāpesi, kāle pana na vassāpesi, sassāni na sammā sampajjanti. Sakalaraṭṭhavāsino tassa vūpasamanatthaṃ anusaṃvaccharaṃ balikammaṃ karontā vasanatthāya cassa ekaṃ gehaṃ akaṃsu. Satthāpi teneva titthena uttaritvā bhikkhusaṃghaparivuto "tasmiṃyeva padese rattiṃ vasissāmī"ti agamāsi.

Athāyaṃ thero "caṇḍo kirettha nāgarājā"ti sutvā "imaṃ nāgarājānaṃ dametvā nibbisevanaṃ katvā satthu vasanaṭṭhānaṃ paṭiyādetuṃ vaṭṭatī"ti nāgassa vasanaṭṭhānaṃ pavisitvā pallaṅkaṃ ābhujitvā nisīdi. Nāgo kujjhitvā "ko nāmāyaṃ muṇḍako mayhaṃ vasanaṭṭhānaṃ pavisitvā nisinno"ti dhūmāyati, thero uttaritaraṃ dhūmāyi. Nāgo pajjali, theropi uttaritaraṃ pajjalitvā tassa tejaṃ pariyādiyi. So "mahanto vatāyaṃ bhikkhū"ti therassa pādamūle nipajjitvā "bhante tumhākaṃ saraṇaṃ gacchāmī"ti āha. Mayhaṃ saraṇagamanakiccaṃ natthi, dasabalassa saraṇaṃ gacchāhīti. So "sādhū"ti saraṇaṃ gato.