In
Nethack, the question of whether your god is
angry with you and what to do about it causes considerable
confusion. You may hear things like "The gods don't like you killing your
pet." You may even have killed your pet yourself, then tried to convert an
altar, "had a strong feeling that your god was angry", and been converted yourself. In fact, if you killed the pet in normal
combat the penalty was -15 to alignment and -1 to luck, and you were converted because your alignment was
negative.
The divine wrath to which I refer is the state in which a wand or potion of enlightenment will tell you that your god is angry with you. It is easily confused with bad alignment, bad luck, or even not being able to pray because your prayer timeout has not expired yet. Many actions which you might think of as incurring divine wrath actually carry alignment or luck penalties instead.
The difference is important because angry gods remain angry and will never again answer your prayers until they are appeased. Bad alignment will go away as you kill hostile monsters, and if you have no luckstone or a blessed one bad luck will fade with time, but an angry deity can only be placated by sacrificing tough monsters until he/she "seems mollified". (If you have a feeling of inadequacy, your sacrifice wasn't tough enough.)
Angering your god has another very annoying side-effect; you will lose all your divine protection.
Fortunately, there are only two common ways to anger your god. The most common is to pray before your prayer timeout has expired. Any unsuccessful prayer will anger your god, even if you merely feel that he/she is displeased. The other is to displace your pet in such a manner as to cause it to die - you'll see the message "You feel guilty about losing your pet like this".