Dutiyakāmabhūsutta
Ekaṁ samayaṁ āyasmā kāmabhū macchikāsaṇḍe viharati ambāṭakavane. Atha kho citto gahapati yenāyasmā kāmabhū tenupasaṅkami; upasaṅkamitvā ekamantaṁ nisīdi. Ekamantaṁ nisinno kho citto gahapati āyasmantaṁ kāmabhuṁ etadavoca: “kati nu kho, bhante, saṅkhārā”ti? “Tayo kho, gahapati, saṅkhārā— kāyasaṅkhāro, vacīsaṅkhāro, cittasaṅkhāro”ti. “Sādhu, bhante”ti kho citto gahapati āyasmato kāmabhussa bhāsitaṁ abhinanditvā anumoditvā āyasmantaṁ kāmabhuṁ uttariṁ pañhaṁ apucchi: “katamo pana, bhante, kāyasaṅkhāro, katamo vacīsaṅkhāro, katamo cittasaṅkhāro”ti? “Assāsapassāsā kho, gahapati, kāyasaṅkhāro, vitakkavicārā vacīsaṅkhāro, saññā ca vedanā ca cittasaṅkhāro”ti.
With Kāmabhū (2nd)
At one time Venerable Kāmabhū was staying near Macchikāsaṇḍa in the Wild Mango Grove. Then Citta the householder went up to Venerable Kāmabhū, sat down to one side, and said to him: “Sir, how many processes are there?” “Householder, there are three processes. The physical process, the verbal process, and the mental process.” Saying “Good, sir,” Citta approved and agreed with what Kāmabhū said. Then he asked another question: “But sir, what is the physical process? What’s the verbal process? What’s the mental process?” “Breathing is a physical process. Placing the mind and keeping it connected are a verbal process. Perception and feeling are a mental process.”