From Three Parable of the Greedy Sons, p. 144-45, Tales of the Dervishes by Idries Shah (Octagon Press, 1967): There was once a hard-working and generous farmer who had several idle and greedy sons. On his deathbed he told them that they would find his treasure if they were to dig in a certain field. As soon as the old man was dead, the sons hurried to the fields, which they dug up from one end to another, and with increasing desperation and concentration when they did not find the gold in the place indicated.
But they found no gold. Realizing that in his generosity their father had given his gold away during his lifetime, they abandoned the search. Finally, it occurred to them that, since the land had been prepared, they might as well now sow a crop. […] They sold this crop and prospered that year.
After the harvest was in, the sons thought again about the bare possibility that they might have missed the buried gold, so they dug up their fields, with the same result.
After several years they became accustomed to labour, and to the cycle of the seasons, something which they had not understood before. Now they understood the reason for their father’s method of training them, and they became honest and contented farmers. Ultimately they found themselves possessed of sufficient wealth no longer to wonder about the hidden hoard.
Thus it is with the teaching of the understanding of human destiny and the meaning of life. The teacher, faced with impatience, confusion and covetousness on the part of the students, must direct them to an activity which is known by him to be constructive and beneficial to them, but whose true function and aim is often hidden from them by their own rawness.
This story, underlining the claim that a person may develop certain faculties in spite of his attempts to develop others, is unusually widely known. This may be because it carries the preface, “Those who repeat it will gain more than they know.”
It was published both by the Franciscan, Roger Bacon (who quotes the Sufi philosophy and taught at Oxford, from which he was expelled by order of the Pope) and the seventeenth century chemist Boerhaave.
This version is attributed to the Sufi, Hasan of Basra, who lived nearly twelve hundred years ago.