Now a certain monk was once sick with dysentery, and he lay fouled in his own urine and excrement. As the Blessed One was going the round of the lodgings with the venerable Ananda as his attendant monk, he came to that monk's dwelling. When he saw him lying where he was, he went up to him and said, "What is your sickness, monk?"
"It is dysentery, Blessed One."
"But, monk, have you no attendant?"
"No, Blessed One."
"Why do the monks not look after you, monk?"
"I am of no use to the monks, Lord; that is why they do not look after me."
Then the Blessed One said to the venerable Ananda, "Ananda, go and fetch some water. Let us wash this monk."
"Even so, Lord," the venerable Ananda replied, and he brought some water.
The Blessed One poured out the water and the venerable Ananda washed the monk. Then the Blessed One took him by the head and the venerable Ananda took him by the feet, and they raised him up and put him on a bed.
With this as the occasion and this as the reason, the Blessed One summoned the monks and asked them, "Monks, is there a monk sick in a certain dwelling?"
"There is, Blessed One."
"What is that monk's illness?"
"He has dysentery, Lord."
Has he anyone to look after him?"
"No, Blessed One."
"Why do the monks not look after him?"
"Lord. that monk is of no use to the monks; that is why they do not look after him."
"Monks, you have neither mother nor father to look after you. If you do not look after each other, who will look after you? Let him who would look after me look after one who is sick. If he has a preceptor, his preceptor should as long as he lives look after him until his recovery. His teacher, if he has one, should do likewise. Or his co-resident, or his pupil, or one who has the same preceptor, or one who has the same teacher. If he has none of these, the Sangha should look after him. Not to do so is an offence of wrongdoing.
"When a sick man has five qualities, he is hard to look after: he does what is unsuitable; he does not know the measure of what is suitable; he does not take medicine; he does not disclose his illness to his sick-nurse who seeks his welfare, or tell him that he is better when it is so, or worse when it is so, or the same when it is so; he is of a type unable to endure arisen bodily feelings that are painful, harsh, racking, piercing, disagreeable, unwelcome and menacing to life. When a sick man has the five opposite qualities, he is easy to look after.
~The Buddha, in The Mahavagga