Deals damage and debuffs an enemy
Judgment is our main single target damaging ability and should be used on cooldown if you're running the Judgment of Light talent. If you run Holy Prism instead, this ability will not help your healing at all but still provides a lot of single target damage so it remains a good use of a GCD.
Heals an ally but damages you
People are often scared to use this heal since it does damage to you, but the damage dealt is fairly small and the mana cost is very low, making it a strong choice for emergency spot healing outside of wings or during heavy movement.
Heals an ally (slow cast)
Holy Light is a slow, hard cast single target heal and should also be what we use most of our
Infusion of Light procs on. Use this mainly for tank healing when you have an Infusion proc and only the tank is taking damage. Casting this on your Beacon target will generate 1 Holy Power.
Heals an ally (fast cast)
Flash of Light should only ever be used in emergency situations where you need immediate healing, have no Holy Power, Holy Shock is on CD and you're too low health to Light of the Martyr. Just like Holy Light, casting this on your Beacon target will generate 1 Holy Power.
Deals damage to all enemies within the effect
Keeping consecration down will provide a fairly substantial dps increase, but offers no boost to your healing so it is definitely lower on the priority list for raiding. Still, any time you can spare the GCD this will help your overall damage a fair amount, even on single target.
Reduces all damage you take by 20% for 8 sec
This is your main defensive, which is free to cast and off the GCD. With the Unbreakable Spirit talent, it's on an extremely low 42 second cooldown so you should be using it very frequently. Any time you know any type of significant damage is incoming don't hesitate to use it.