Buddhist Scriptures, by E.J. Thomas, [1913], at sacred-texts.com
On the subject of this discourse and the two following compare the Introduction, p. 14.
Thus have I heard: The Lord was once dwelling near Sāvatthi, at Jetavana in the park of Anāthapindika. Now the elder Mālunkyāputta had retired from the world, and as he meditated the thought arose: "These theories have been left unexplained by the Lord, set aside, and rejected, whether the world is eternal or not eternal, whether the world is finite or not, whether the soul (life) is the same as the body, or whether the soul is one thing and the body another, whether a Buddha (Tathāgata) exists after death or does not exist after death, whether a Buddha both exists and does not exist after death, and whether a Buddha is non-existent and not non-existent after death—these things the Lord does not explain to me, and that he does not explain them to me does not please me, it does not suit me. I will approach the Lord, and ask about this
matter. . . . If the Lord does not explain to me, I will give up the training, and return to a worldly life."
[When Mālunkyāputta had approached and put his questions the Lord replied:] "Now did I, Mālunkyāputta, ever say to you, 'Come, Mālunkyāputta, lead a religious life with me, and I will explain to you whether the world is eternal or not eternal [and so on with the other questions]?'" "You did not, reverend sir." "Anyone, Mālunkyāputta, who should say 'I will not lead a religious life with the Lord, until the Lord explains to me whether the world is eternal or not eternal [etc.] . . .' that person would die, Mālunkyāputta, without its being explained. It is as if a man had been wounded by an arrow thickly smeared with poison, and his friends, companions, relatives, and kinsmen were to get a surgeon to heal him, and he were to say, 'I will not have this arrow pulled out, until I know by what man I was wounded, whether he is of the warrior caste, or a brahmin, or of the agricultural, or the lowest caste.' Or if he were to say, 'I will not have this arrow pulled out until I know of what name or family the man is . . . or whether he is tall, or short, or of middle height . . . or whether he is black, or dark, or yellowish . . . or whether he comes from such and such a village, or town, or city . . . or until I know whether the bow with which I was
wounded was a chāpa or a kodanda, or until I know whether the bow-string was of swallow-wort, or bamboo-fibre, or sinew, or hemp, or of milk-sap tree, or until I know whether the shaft was from a wild or cultivated plant . . . or whether it was feathered from a vulture's wing or a heron's or a hawk's, or a peacock's, or a sithilahanu-bird's . . . or whether it was wrapped round with the sinew of an ox, or of a buffalo, or of a ruru-deer, or of a monkey . . . or until I know whether it was an ordinary arrow, or a razor-arrow, or a vekanda, or an iron arrow or a calf-tooth arrow, or one of a karavīra leaf.' That man would die, Mālunkyāputta, without knowing all this.
"It is not on the view that the world is eternal, Mālunkyāputta, that a religious life depends; it is not on the view that the world is not eternal that a religious life depends. Whether the view is held that the world is eternal, or that the world is not eternal, there is still re-birth, there is old age, there is death, and grief, lamentation, suffering, sorrow, and despair, the destruction of which even in this life I announce. It is not on the view that the world is finite . . . It is not on the view that a Tathāgata exists after death . . . Therefore, Mālunkyāputta, consider as unexplained what I have not explained, and consider as explained what I have explained. And what, Mālunkyāputta, have I not explained?
[paragraph continues] Whether the world is eternal I have not explained, whether the world is not eternal . . . whether a Tathāgata is both non-existent and not nonexistent after death I have not explained. And why, Mālunkyāputta, have I not explained this? Because this, Mālunkyāputta, is not useful, it is not concerned with the principle of a religious life, does not conduce to aversion, absence of passion, cessation, tranquillity, supernatural faculty, perfect knowledge, Nirvana, and therefore I have not explained it.
"And what, Mālunkyāputta, have I explained? Suffering have I explained, the cause of suffering, the destruction of suffering, and the path that leads to the destruction of suffering have I explained. For this, Mālunkyāputta, is useful, this is concerned with the principle of a religious life; this conduces to aversion, absence of passion, cessation, tranquillity, supernatural faculty, perfect knowledge, Nirvana, and therefore have I explained it. Therefore, Mālunkyāputta, consider as unexplained what I have not explained, and consider as explained what I have explained." Thus spoke the Lord, and with joy the elder Mālunkyāputta applauded the words of the Lord. (Majjh. Nik. I. 426 ff.)