When you are casting a miracle they will fall into one of four types (Creation, Destruction, Transformation or Control). You need to select one of the four for your God to be attuned with (resulting in a cost reduction for miracles), two of these that your God is neutral with (no cost break or cost increase) and which of these your God is opposed to (resulting in a cost increase).
Creation: Miracles using creation involve something coming from nothing. (An army of clay warriors appearing on the battlefield, divine armour appearing on an army etc).
Destruction: Nothing short of purely destructive power, where other miracles can be harnessed to cause harm, this purely focuses upon it (Rain of fire razes a village, weapons crumble and rust in the hands of the enemy).
Transformation: Bending and altering what already exists into something new (A forest coming alive to defend the faithful, rain turning into acid as it falls, a hastily erected wall of mud turns into granite)
Control: The most subtle of miracle styles, control focuses on bending the human mind (granting a prophet the ability to see far off lands, making enemy soldiers change sides or run away).
Secondly we have Tribe Breakdown
With each tribe being made up of 100 people, you must selecting 30% to be better than average in either body, spirit or mind. Body are the strong, spirit the most faithful and mind the most intelligent. The game assumes a 10% of each type, thus 10 who specialize in each area, however it is up to you how you break down that 30.