Buddha Answers to a Deva

On a certain day the Blessed One dwells in Jetavana. 
The Deva asked Questions that the Blessed One answer:
The Deva said: What is the sharpest sword? What is the deadliest poison? what is the fiercest Fire? what is the darkest night? The Blessed One replies: A word spoken is wrath is the sharpest sword, covetousness is the deadliest poison, passion is the fiercest fire, ignorance is the darkest night.
The Deva said: who gains the greatest benefit? who loses most? which armour is invulnerable? what is the best weapon? The Blessed One replies: He is the greatest gainer who to others, and he loses most who greedily receives without gratitude. Patient is an invulnerable Armour, wisdom the best weapon.
The Deva said: who is the most dangerous thief? what is the most precious treasure? who is most successful in taking away by violence not only on earth, but also in heaven? what is the secures treasure-trove? The Blessed One replies: Evil thought is the most dangerous thief; virtue is the most precious treasure. The mind takes possession everything not only on earth but on heaven, and immortality is its securest treasure-trove.
The Deva said: What is attractive? what is disgusting? what is the most horrible pain? what is the greatest enjoyment? The Blessed One answer: Good is Attractive, evil is disgusting. A bad conscience is the most tormenting pain; deliverance is the height of bliss.
The Deva asked: What causes ruin to the world? what break off friendships? what is the most violent fever? who is the best physician? The Blessed One answer: Ignorance causes ruin to the world. Envy and selfishness break off friendships. Hatred is the most violent fever, and the Buddha is the best physician.
The Deva then asked: Now i have only one doubt to be solved; clear it away; What is it the fire can neither burn, nor moisture corrode, nor wind crush down, but able to reform the whole world? The Blessed One replies: Blessings! Neither fire, not moisture nor wind can destroy, The blessing of a good Deed, and blessing reform the whole world.