‘Venerable Nāgasena, that one quality of the road spider you say he ought to have, which is it?’

‘Just, O king, as the road spider weaves the curtain of its net on the road, and whatsoever is caught therein, whether worm, or fly, or beetle, that does he catch and eat; just so, O king, should the strenuous Bhikshu, earnest in effort, spread the curtain of the net of self-possession over the six doors (of his six senses), and if any of the flies of evil are caught therein, there should he seize them. This, O king, is the quality of the road spider he ought to have. For it was said, O king, by Anuruddha, the Elder:

“His heart should he shut in, at its six doors,
By self-possession, best and chief of gifts,
Should any evil thoughts be caught within,
Them by the sword of insight should he slay.”’