While out collecting his morning food, a farmer basically tells the Buddha that if he wants to eat he should grow his own food. The Buddha responds with a deep Dhamma teaching.
From SN 7:11 Kasi Bharadvaja the farmer:
Thereupon the brahman addressed the Blessed One in a stanza:
1. "You profess to be a plowman, yet your plow we do not see; asked about your plow and the rest, tell us of them that we may know."
2. "Faith is my seed, austerity the rain, wisdom my yoke and plow, modesty is the pole, mind the strap, mindfulness is my plowshare and goad.
3. "Controlled in speech and conduct, guarded in deed and speech, abstemious in food, I make truth my weed cutter; arahantship, my deliverance complete.
4. "Exertion, my team in yoke, draws me to Nibbana's security, and on it goes without stopping, wither gone one does not suffer.
5. "Thuswise is this plowing plowed which bears the fruit of Deathlessness; having plowed this plowing one is freed from every ill."
Read the whole sutta on AccessToInsight.org