Mahapadanasutta 2.18.1

2.18.1

Atha kho, bhikkhave, vipassissa bodhisattassa vāsūpagatassa rahogatassa paṭisallīnassa evaṃ cetaso parivitakko udapādi:

Then as Vipassī, the one intent on awakening, was in private retreat in his dwelling, this thought came to his mind,