• Upassuti Sutta

Once when the Buddha was staying in the Giñjakāvasatha in Nātikā, he meditated in solitude and uttered a teaching setting forth how, from the objects and the senses, arise consciousness and contact and, ultimately, the whole body of Ill. A certain monk overheard this, and when the Buddha saw him, he asked the monk to learn the discourse by heart and bear it in mind, because it would lead to the righteous life. S. iv.90f.