Divine spellcasters prepare their spells in largely the same manner as wizards, but with a few differences.
Time of Day: A divine spellcaster chooses and prepares spells ahead of time, just as a wizard does. However, divine spellcasters do not require a period of rest to prepare spells. Instead, the character chooses a particular part of the day to pray and receive spells. Some deities set the time or impose other special conditions for granting spells to their clerics. If some event prevents the character from praying at the proper time, the character must do so as soon as possible. If the character does not stop to pray for spells at the first opportunity, the character must wait until the next day to prepare spells.
Spell Selection and Preparation: A divine spellcaster selects and prepares spells ahead of time through prayer and meditation at a particular time of day. The time required to prepare spells is the same as for a wizard (1 hour), as is the requirement for a relatively peaceful environment in which to perform the preparation. A divine spellcaster does not have to prepare all his or her spells at once. However, the character cannot fill a slot that is empty because the character has cast a spell or abandoned a previously prepared spell at any time other than the first daily spell preparation.
However, the character can spontaneously cast cure or inflict spells in place of certain prepared spells (see Spontaneous Casting of Cure and Inflict Spells, below).
Divine spellcasters do not require spellbooks. However, a character's spell selection is limited to the spells on the list for the character's class. Clerics also have access to two domains determined during their character creation. Each domain gives a cleric access to a domain spell at each spell level, as well as a special granted power. With access to two domain spells at each given spell level-one from each of the cleric's two domains-a cleric must prepare, as an extra domain spell, one or the other each day for each level of spell the cleric can cast. If a domain spell is not on the Cleric Spells List, it can only be prepared in a domain slot.
Recent Casting Limit: As with arcane spells, at the time of preparation any spells cast within the previous 8 hours count against the number of spells that can be prepared.
Spontaneous Casting of Cure and Inflict Spells: A good cleric (or a cleric of a good deity) can spontaneously cast a cure spell in place of a prepared spell of the same level or higher, but not in place of an extra domain spell. An evil cleric (or a cleric of an evil deity) can spontaneously cast an inflict spell in place of a prepared nondomain spell of the same level or higher. Each neutral cleric of a neutral deity either spontaneously casts cure spells like a good cleric or inflict spells like an evil one, depending on which option the player chooses when creating the character.
Divine spells can be written down and deciphered just as arcane spells can (see Arcane Magical Writings.) Any character with the Spellcraft skill can attempt to decipher the divine magical writing and identify it. However, only characters who have the spell in question (in its divine form) on their class-based spell lists can cast a divine spell from a scroll.
Divine spellcasters most frequently gain new spells in one of the following two ways:
Spells Gained at a New Level: Characters who can cast divine spells undertake a certain amount of study of divine magic between adventures. Each time a character receives a new level of divine spells, the character learns new spells from that level automatically.
Independent Research: The character also can research a spell independently, much as an arcane spellcaster can. Only the creator of such a spell can prepare and cast it, unless he decides to share it with others. Some such creators share their research with their churches, but others do not. The character can create a magic scroll (provided the character has the Scribe Scroll feat) or write a special text similar to a spellbook to contain spells the character has independently researched. Other divine spellcasters who find the spell in written form can learn to cast it, provided they are of sufficient level to do so and are of the same class as the creator. The process requires deciphering the writing (see Arcane Magical Writings.)