The Yoruba theology resides mainly in the believe of a one God, who created everything that exists. From Him came several energies who take care of every detail of the Universe, those are called by the Yoruban believers, Irunmole and Orishas.

In the Yoruba system of belief, before you're born you have already decided what is going to happen with your life, this happens through Ori, which decide what is going to be the main objective in the new life you're begining. Using the different energies of the Universe, we can achieve easily the needed balance to get to that final objective pre defined by ourselves, meaning living life in balance, with health, happiness and wealth.

Once you come to the earthly plane, your body is formed by three elements: Emí (spirit), Orí (soul) and Ará (body). The Emí and the Orí live inside the Ará but separated. Orí has the knowledge and the wisdom of passed lifes, it keeps closed to ones consciousness until death.

Emí allows us to our internal dialogue, it stores memories from this encarnation, and it goes aside from our counsciousness when we incorporate the Orisha, then he goes out the Ará.

When we die, Emí and Orí becomes one and leave the Ará who will transform in a dead body (Okú). Once they're only one energy they'll wait for the fate that will come to them, meaning returning to Aiyé transformed in an spirit (eggun) and wait for the reincarnation (Atúnwá), or if Aragbá Orún (Way to Orún), to get to the Ará Orún state (habitant of the Orún) with the Orishas. These state is only achieved after several reincarnations, until ones Emí has a state pure enough to become an habitant of Orún.

Every dweller of Aiyé, according to their behaviour in life can be considered as an omoluabí or an ajogun. Those who broked the laws and had a despicable behaviour during life, become ajogun or dark spirits, among those are:

Iku: The Death. King of the Ajogun.
Arun: The disease.
Ofo: The greed.
Epe: The hatress.
Ewon: The selfishness.
Egba: The loneliness.

The omoluabí are those that were rightous in the life, but anyway commited some mistakes, they're considered kind spirits and can be adored as family ancestors.