[563] Now at that time the uncle of a certain bhikkhu was sick in the army. He sent a messenger to that bhikkhu, saying: "I am sick in the army. Let the venerable one come; I wish for the venerable one's coming."
Then it occurred to that bhikkhu: "A training rule (sikkhāpada) has been laid down by the Blessed One for bhikkhus: 'One should not go to see an army marched out.' Yet this uncle of mine is sick in the army. How, then, should I proceed?"
They informed the Blessed One of this matter. Then the Blessed One, on account of that occasion, in that connection, having given a talk on the Dhamma, addressed the bhikkhus: "I allow you, bhikkhus, to go to an army when there is a suitable reason. And thus, bhikkhus, should you recite this training rule:
'Whatever bhikkhu should go to see an army marched out, except for a suitable reason, there is an offense of pācittiya.'"
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.