Aligned priests, @, tend the temples of NetHack. They will always appear as "priest of (deity)" and will be generated with a mace, small shield, a robe (or occasionally cloak of protection or cloak of magic resistance), a small amount of gold, and often a number of spellbooks. Priests tending temples will always be peaceful (except for the high priest of Moloch); however, large numbers of priests of Moloch appear in Moloch's Sanctum, and a large number of assorted hostile priests will appear on the Astral Plane.
Occurrence of temples with priestsEdit
Besides random generation, there are two levels which always generate temples: Minetown has a temple of a random alignment, and the Valley of the Dead has a temple of Moloch. Depending on your role, there may also be a temple in your Quest. However, as these levels are eligible to leave bones files, it is possible not to find a peaceful aligned priest in a given game. If the temple in Minetown bones file has been converted, the priest may be peaceful, and wandering about the level. However, #chatting to a wandering priest will make him hostile; see the discussion of chatting below.
Killing a temple priest safelyEdit
Attempting to convert the temple's altar will anger the priest. Directly attacking a peaceful priest is a bad idea, as their god will strike you with lightning; however, the bolt can be deflected if you have reflection. Thus, one of the better ways is to let your pet kill the priest, if it's powerful enough.
A good way to convert a temple is to get a scroll of earth (two are guaranteed to be generated on the first level of Sokoban), get reflection (also possibly from Sokoban), stand in the temple so that the priest(ess) is not adjacent to you, then read the scroll. Optionally, push the boulders to confine the priest to one particular square. Engrave or burn an Elbereth on your fighting spot to protect you from the summoned ants. Now you can blind yourself (be sure to have telepathy) and zap or fire things at the priest without the risk of being paralyzed or getting hit with the mace. You will still get the god's lightning strikes! If you lack reflection and shock resistance, but have a ray attack, you might want to bring the temple's walls between you and the altar, and use bounces instead. Once the priest is killed, you can start sacrificing. If you are playing a chaotic human, you should try to #offer the priest's corpse, since it will have a 100% chance of converting the altar.
Still another way is to poison the priest with a stinking cloud. Be careful, you need to see the center spot, but you want shelter from the god's lightning, which may originate from positions other than the altar. 
If you wish to kill a priest yourself and avoid the penalty for murder, polymorphing the priest to a non-human will allow you to do so, though you will still be struck by lightning by their god.
Killing a co-aligned priest(ess) will not give you a Luck penalty beyond that imposed for murder, but it will remove all your protection. But that's generally a bad idea anyway. A better approach is to trap him.
If you #chat to a priest, a variety of effects can result. If you have no gold in open inventory and are co-aligned, they will "give you two bits for an ale" (two zorkmids) if they have at least two gold (or one bit if they have exactly one gold), and will "preach the virtues of poverty" if they have no gold; if you are cross-aligned, they will ignore you. If you are carrying gold in open inventory, they will prompt you for a contribution to the temple; depending on the amount of gold you offer, one of several events will happen:
|0 or less||"Thou shalt regret thine action!" If the priest is co-aligned, you lose one alignment point.|
|Positive but less than 200 times current experience level||If this is less than half your visible gold, nothing happens.
Otherwise, exercises wisdom.
"I thank thee for thy contribution."
|At least 200 but less than 400 times current experience level||"Thou art indeed a pious individual." If this is more than half your visible gold, you are granted 500-999 turns of clairvoyance. If additionally, the priest is coaligned and you have sinned or worse, you gain one point of alignment. "I bestow upon thee a blessing."|
|At least 400 but less than 600 times current experience level||
If you have never bought intrinsic protection, earn 2-4 points of protection. Otherwise, if you have less than 9 protection, or less than 20 with a 1-in-current-protection chance, earn an additional point of protection; if not, fall through to next case. (This is the preferred way to obtain protection.)
"Thy devotion has been rewarded."
|At least 600 times current experience level||"Thy selfless generosity is deeply appreciated."If this is more than half your gold and the temple is co-aligned:
However, if the priest is not in a temple or the temple has been desecrated, #chatting to the priest will make him hostile. Listen carefully to the message you get when entering the temple. This should generally apply only to priests in bones files and the peaceful coaligned priests on the Astral Plane, as the priest will already be hostile if you have desecrated the temple yourself. Even if you re-convert the temple's altar to the priest's religion and pacify him, he will still get angry on chatting.
[...] For the two priests were talking exactly like priests,
piously, with learning and leisure, about the most aerial
enigmas of theology. The little Essex priest spoke the more
simply, with his round face turned to the strengthening stars;
the other talked with his head bowed, as if he were not even
worthy to look at them. But no more innocently clerical
conversation could have been heard in any white Italian cloister
or black Spanish cathedral. The first he heard was the tail of
one of Father Brown's sentences, which ended: "... what they
really meant in the Middle Ages by the heavens being
incorruptible." The taller priest nodded his bowed head and
said: "Ah, yes, these modern infidels appeal to their reason;
but who can look at those millions of worlds and not feel that
there may well be wonderful universes above us where reason is