‘Venerable Nāgasena, that one quality of the land tortoise which you say he ought to take, which is it?’
‘Just, O king, as the land tortoise, being afraid of the water, frequents places far from it, and by that habit of avoiding water its length of life is kept undiminished; just so, O king, should the strenuous Bhikshu, earnest in effort, seeing the danger in the want of earnestness, be mindful of the advantages that distinguish earnestness. For by that perception of danger in carelessness, his Samanaship fades not away, but rather does he go forward to Nirvāṇa itself. This, O king, is the quality of the land tortoise he ought to have. For it was said, O king, by the Blessed One, the god over all gods, in the Dhammapada:
“The Bhikshu who in earnestness delights,
Who sees the danger of indifference,
Shall fall not from his high estate away,
But in the presence of Nirvāṇa dwell.”’