Even as the rain does penetrate
a house that's badly thatched,
likewise lust does penetrate
the mind uncultivated.
-Dhammapada Verse 13
Explanation: It is quite necessary that a house should have a well-thatched roof. If the thatching is weak, rain seeps through the house. Just as a badly thatched roof lets in the rain, the uncultured temperament too is open to passions. The temperament that is not cultured is penetrated easily by lust.
