On one occasion, Venerable Maha Kaccana was living at Madhura in the Gunda Grove. King Avantiputta of Madhura heard: "The recluse Kaccana is living at Madhura in the Gunda Grove. A good report of Master Kaccana has been spread to this effect: 'He is wise, accomplished, sagacious, learned, articulate, and insightful; he is aged and he is an arahant. It is good to see such arahants.'"
Then King Avantiputta of Madhura had a number of state carriages made ready, and mounting a state carriage, he drove out from Madhura with the full royalty entourage in order to see the venerable Maha Kaccana. He went thus as far as the road was passable for carriages, and then he got down from his carriage and went forward on foot to the venerable Maha Kaccana. He exchanged greetings with him, and when this courteous and amiable talk was finished, he sat down at one side and said:"Master Kaccana, the brahmins say thus: 'Brahmins are the highest caste, those of any other caste are inferior; brahmins are the fairest caste, those of any other caste are dark; only brahmins are purified, not non-brahmins; brahmins alone are the sons of Brahma, the offspring of Brahma, born of his mouth, born of Brahma, created by Brahma, heirs of Brahma.' What does Master Kaccana say about that?"
Venerable Kaccana: "It is just a saying in the world, great king, that 'Brahmins are the highest caste...heirs of Brahma.' And there is a way whereby it can be understood how that statement of the brahmins is just a saying in the world. "What do you think, great king? If a noble prospers in wealth, grain, silver, or gold, will there be nobles who rise before him and retire after him, who are eager to serve him, who seek to please him and speak sweetly to him, and will there also be brahmins, merchants, and workers who do likewise?" King: "There will be, Master Kaccana." Venerable Kaccana:"Similarly, what do you think, great king? If a brahmin prospers in wealth, grain, silver, or gold, will there be brahmins who rise before him and retire after him, who are eager to serve him, who seek to please him and speak sweetly to him, and will there also be merchants, workers, and nobles who do likewise?" King: "There will be, Master Kaccana."
Venerable Kaccana: "What do you think, great king? If a merchant prospers in wealth, grain, silver, or gold, will there be merchants who rise before him and retire after him, who are eager to serve him, who seek to please him and speak sweetly to him, and will there also be workers, nobles, and brahmins who do likewise?" King: "There will be, Master Kaccana."
Venerable Kaccana: "What do you think, great king? If a worker prospers in wealth, grain, silver, or gold, will there be workers who rise before him and retire after him, who are eager to serve him, who seek to please him and speak sweetly to him, and will there also be nobles, brahmins, and merchants who do likewise?" King: "There will be, Master Kaccana."
Venerable Kaccana: "What do you think, great king? If that is so, then are these four castes (noble, brahmin, merchant and worker) all the same, or are they not, or how does it appear to you in this case?" King: "Surely if that is so, Master Kaccana, then these four castes are all the same: there is no difference between them at all that I see." Venerable Kaccana: "That is a way, great king, whereby it can be understood how that statement of the brahmins is just a saying in the world. What do you think, great king? Suppose a noble were to kill living beings, take what is not given, misconduct himself in sensual pleasures, speak falsely, speak maliciously, speak harshly, gossip, be covetous, have a mind of ill will, and hold wrong view. On the dissolution of the body, after death, would he likely to reappear in a state of deprivation, in an unhappy destination, in perdition, even in hell, or not, or how does it appear to you in this case?" King: "If a noble were such, Master Kaccana, he would likely to reappear in a state of deprivation, in an unhappy destination, in perdition, even in hell. That is how it appears to me in this case, and thus I have heard from the arahants."
Venerable Kaccana: "What do you think, great king? Suppose a brahmin...a merchant... a worker were to kill living beings...and hold wrong view. On the dissolution of the body, after death, would he likely to reappear in a state of deprivation, in an unhappy destination, in perdition, even in hell, or not, or how does it appear to you in this case?" King: "If a brahmin...a merchant...a worker were such, Master Kaccana, he would likely to reappear in a state of deprivation, in an unhappy destination, in perdition, even in hell. That is how it appears to me in this case, and thus I have heard from the arahants."
Venerable Kaccana: "What do you think, great king? If that is so, then are these four castes (noble, brahmin, merchant and worker) all the same, or are they not, or how does it appear to you in this case?" King: "Surely if that is so, Master Kaccana, then these four castes are all the same: there is no difference between them at all that I see."
Venerable Kaccana: "That is also a way, great king, whereby it can be understood how that statement of the brahmins is just a saying in the world. What do you think, great king? Suppose a noble were to abstain from killing living beings, from taking what is not given, from misconduct in sensual pleasures, from false speech, from malicious speech, from harsh speech, and from gossip, and were to be uncovetous, to have a mind without ill will, and to hold right view. On the dissolution of the body, after death, would he likely to reappear in a happy destination, even in the heavenly world, or not, or how does it appear to you in this case?" King: "If a noble were such, Master Kaccana, he would likely to reappear in a happy destination, even in the heavenly world. That is how it appears to me in this case, and thus I have heard from the arahants."
Venerable Kaccana: "What do you think, great king? Suppose a brahmin...a merchant... a worker were to abstain from killing living beings... and to hold right view. On the dissolution of the body, after death, would he likely to reappear in a happy destination, even in the heavenly world, or not, or how does it appear to you in this case?" King: "If a brahmin...a merchant...a worker were such, Master Kaccana, he would [be likely to] reappear in a happy destination, even in the heavenly world. That is how it appears to me in this case, and thus I have heard from the arahants."
Venerable Kaccana: "What do you think, great king? If that is so, then are these four castes all the same, or are they not, or how does it appear to you in this case?" King: "Surely if that is so, Master Kaccana, then these four castes are all the same: there is no difference between them at all that I see." Venerable Kaccana: "That is also a way, great king, whereby it can be understood how that statement of the brahmins is just a saying in the world.What do you think, great king? Suppose a noble were to break into houses, plunder wealth, commit burglary, ambush highways, or seduce another's wife, and if your men arrested him and produced him, saying: 'Sire, this is the culprit; command what punishment for him you wish,' how would you treat him?" King: "We would have him executed, Master Kaccana, or we would have him fined, or we would have him exiled, or we would do with him as he deserved. Why is that? Because he has lost his former status of a noble, and is simply reckoned as a robber."
Venerable Kaccana: "What do you think, great king? Suppose a brahmin...a merchant...a worker were to break into houses...or seduce another's wife, and if your men arrested him and produced him, saying: 'Sire, this is the culprit; command what punishment for him you wish,' how would you treat him?" King: "We would have him executed, Master Kaccana, or we would have him fined, or we would have him exiled, of we would do with him as he deserved. Why is that? Because he has lost his former status of a brahmin...a merchant...a worker, and is simply reckoned as a robber."
Venerable Kaccana: "What do you think, great king? If that is so, then are these four Castes all the same, or are they not, or how does it appear to you in this case?" King: "Surely if that is so, Master Kaccana, then these four castes are all the same; there is no difference between them at all that I see!"
Venerable Kaccana: "That is also a way, great king, whereby it can be understood how that statement of the brahmins is just a saying in the world. What do you think, great king? Suppose a noble, having shaved off his hair and beard, put on the yellow robe, and gone forth from the home life into homelessness, were to abstain from killing living beings, from taking what is not given, and from false speech. Refraining from eating at night, he would eat only in one part of the day, and would be celibate, virtuous, of good character. How Would you treat him?"
King: "We would pay homage to him, Master Kaccana, or we would rise up for him, or invite him to be seated; or we would invite him to accept robes, alms food, resting place, and medicinal requisites; or we would arrange for him lawful guarding, defence, and protection. Why is that? Because he has lost his former status of a noble, and is simply reckoned as a recluse." Venerable Kaccana: "What do you think, great king? Suppose a brahmin...a merchant... a worker, having shaved off his hair and beard...and would be celibate, virtuous, of good character. How would you treat him?" King: "We would pay homage to him, Master Kaccana, or rise up for him, or invite him to be seated; or we would invite him to accept robes, alms food, resting place, and medicinal requisites; or we would arrange for him lawful guarding, defence, and protection. Why is that? Because he has lost his former status of a brahmin...a merchant...a worker, and is simply reckoned as a recluse."
Venerable Kaccana: "What do you think, great king? If that is so, then are these four castes all the same, or are they not, or how does it appear to you in this case?" King: "Surely if that is so, Master Kaccana, then these four castes are all the same; there is no difference between them at all that I see." Venerable Kaccana: "That is also a way, great king, whereby it can be understood how that statement of the brahmins is just a saying in the world." When this was said, King Avantiputta of Madhura said to the venerable Maha Kaccana: "Magnificent, Master Kaccana! Magnificent, Master Kaccana! Master Kaccana has made the Dhamma clear in many ways, as though he were turning upright what had been overthrown, revealing what was hidden, showing the way to one who is lost, or holding up a lamp in the dark for those with eyesight to see forms. I go to Master Kaccana for refuge and to the Dhamma and to the Sangha of bhikkhus. From today let Master Kaccana remember me as a lay follower who has gone to him for refuge for life."
Venerable Kaccana: "Do not go to me for refuge, great king. Go for refuge to that same Blessed One to whom I have gone for refuge." King: "Where is he living now, that Blessed One, accomplished and fully enlightened, Master Kaccana?" Venerable Kaccana: "That Blessed One, accomplished and fully enlightened, has attained to final Nibbana, great king." King:"If we heard that that Blessed One was within ten leagues, we would go ten leagues in order to see that Blessed One, accomplished and fully enlightened. If we heard that that Blessed One was within twenty leagues...thirty leagues...forty leagues...fifty leagues...a hundred leagues, we would go a hundred leagues in order to see that Blessed One, accomplished and fully enlightened. But since that Blessed One has attained to final Nibbana, we go to that Blessed One for refuge and to the Dhamma and to the Sangha of bhikkhus. From today let Master Kaccana remember me as a lay follower who has gone for refuge for life."
In summary, king Avantiputta of Madhurā, visits Venerable Mahā Kaccāna some time after the Buddha's death and questions him regarding the brahmin claims to superiority over other castes. Maha Kaccāna points out that wealth confers power on all, not only on brahmins. A brahmin experiences the result of his actions both good and bad, in this world and in the next, just like members of other castes namely the nobles, merchants and workers. A brahmin ascetic receives the same homage and respect just like an ascetic of other castes. At the end of the discourse, King Avantiputta agreed that all caste members are equal with no difference. The king thanked Maha Kaccana for the teachings and take refuge in the triple gem.
References: 1. www.accesstoinsight.org 2. https://suttacentral.net/ 3. The middle length discourses of the Buddha (Bhikkhu Bodhi)