If a person stays in another’s house even for one night and receives food and drinks, he should not even wish evil for the host. Gratitude is what is praised by good persons (sappurisa).

Whenever prudent people have met a good person they don’t give up his friendship, nor do they spoil the service done to themselves. The fools, however, give up the friendship, and they spoil the service done to themselves.

Even if one would offer the whole earth to an ungrateful person, one could not please him.

Even a lot of service towards the fools is reduced to nothing, for fools are merely ungrateful.

A service is hopeless from one who has no gratitude who does not help in return. Is ungrateful and apathetic. His friendship is not won by the clearest good deed. One should hastily shun him with no bitter thought and angry word.

The wise ones indeed don’t give up the friendship, nor do they spoil the service done to themselves. Even a slight service towards themselves is not disowned, for the wise ones are full of gratitude.

-- The Buddha