Im not an expert of cleric,but here is the builds i heard about,it works really good:25 spirit(for the critical hits,more sp,more mage def)and the rest in End(if you wana support) or Str(if u wana fight).But a cleric with 25 spr,rest str can also support,its just that healing generates aggro and you might want to have extra hp from the pts you put on end to survive that.Im not sure if FULL spr is good...But i THINK it is(never tested).
PS:Personally,my cleric is lvl15 lol.