A cleric of a chaotic, evil, good, or lawful deity has a particularly powerful aura corresponding to the deity’s alignment (see detect evil for details).

Regardless of alignment, any cleric can release a wave of energy by channeling the power of her faith through her holy (or unholy) symbol. This energy can be used to cause or heal damage, depending on the type of energy channeled and the creatures targeted.
 
A good cleric (or a neutral cleric who worships a good deity) channels positive energy and can choose to deal damage to undead creatures or to heal living creatures. An evil cleric (or a neutral cleric who worships an evil deity) channels negative energy and can choose to deal damage to living creatures or to heal undead creatures. A neutral cleric of a neutral deity (or one who is not devoted to a particular deity) must choose whether she channels positive or negative energy. Once this choice is made, it cannot be reversed. This decision also determines whether the cleric can cast spontaneous cure or inflict spells (see spontaneous casting).
 
Channeling energy causes a burst that affects all creatures of one type (either undead or living) in a 30-foot radius centered on the cleric. The amount of damage dealt or healed is equal to 1d6 points of damage plus 1d6 points of damage for every two cleric levels beyond 1st (2d6 at 3rd, 3d6 at 5th, and so on). Creatures that take damage from channeled energy receive a Will save to halve the damage. The DC of this save is equal to 10 + 1/2 the cleric’s level + the cleric’s Charisma modifier. Creatures healed by channel energy cannot exceed their maximum hit point total—all excess healing is lost. A cleric may channel energy a number of times per day equal to 3 + her Charisma modifier. This is a standard action that does not provoke an attack of opportunity. A cleric can choose whether or not to include herself in this effect.
 
A cleric must be able to present her holy symbol to use this ability.

Your touch staves off pain and death, and your healing magic is particularly vital and potent.
 
Granted Powers
 
Rebuke Death (Sp): You can touch a living creature as a standard action, healing it for 1d4 points of damage plus 1 for every two cleric levels you possess. You can only use this ability on a creature that is below 0 hit points. You can use this ability a number of times per day equal to 3 + your Wisdom modifier.
 
Healer’s Blessing (Su): At 6th level, all of your cure spells are treated as if they were empowered, increasing the amount of damage healed by half (+50%). This does not apply to damage dealt to undead with a cure spell. This does not stack with the Empower Spell metamagic feat.
 
Domain Spells: 1st—Cure Light Wounds, 2nd—Cure Moderate Wounds, 3rd—Cure Serious Wounds, 4th—Cure Critical Wounds, 5th—breath of life, 6th—Heal, 7th—regenerate, 8th—Cure Critical Wounds, Mass, 9th—heal (mass).

Your faith is your greatest source of protection, and you can use that faith to defend others. In addition, you receive a +1 resistance bonus on saving throws. This bonus increases by 1 for every 5 levels you possess.
 
Granted Powers
 
Resistant Touch (Sp): As a standard action, you can touch an ally to grant him your resistance bonus for 1 minute. When you use this ability, you lose your resistance bonus granted by the Protection domain for 1 minute. You can use this ability a number of times per day equal to 3 + your Wisdom modifier.
 
Aura of Protection (Su): At 8th level, you can emit a 30-foot aura of protection for a number of rounds per day equal to your cleric level. You and your allies within this aura gain a +1 deflection bonus to AC and resistance 5 against all elements (acid, cold, electricity, fire, and sonic). The deflection bonus increases by +1 for every four cleric levels you possess beyond 8th. At 14th level, the resistance against all elements increases to 10. These rounds do not need to be consecutive.
 
Domain Spells: 1st—sanctuary, 2nd—shield other, 3rd—protection from energy, 4th—spell immunity, 5th—spell resistance, 6th—antimagic field, 7th—repulsion, 8th—mind blank, 9th—prismatic sphere.