The Priest is a spellcaster heavily focused on healing and defensive spells. They gain access to new spells quickly as they advance in level.
Priests have proficiency with a smaller range of weapons than most, but they do have some good options. They are the most suited to melee of all the spell casting roles, as they are usually able to cast with a low rate of spell failure even in heavy armor.
Wisdom is the most important ability score for all Priests, as it controls all aspects of their spellcasting. Constitution is important for Priests who want to survive in melee combat.