Haitians don't call their religion Voodoo, and we won't either. Voodoo is associated with imperialism and colonialism, which go hand in hand with missionization. In colonization/missionization, as the metropole/core subjugates labor, religion converts their souls. Religion is used to legitimize, validate political domination.
Image of voodoo was created by foreigners, especially during U.S. occupation. Voodoo was depicted as cannibalistic and savage. They personified the basic savage prejudices towards Africans in their interpretations of their Voodoo ceremonies. They assumed that if blacks were left on their own, barbarism would reign. Thus, they needed to be controlled. Their labor power was controlled by white American business owners. Their souls were converted to a "civilizing religion" by missionaries.
Haitians adapted to this view of their religion. They realized that could make money from it. Voodoo became a commodity, sold to tourists. You could buy tickets to see bogus ceremonies as "temples" in the capital city, which are also restaurants and bars. Troupes put on "authentic" ceremonies at hotels. It was a theatrical performance, with actors, fire eaters, virtuosos, and erotic dances. Foreigners could satisfy their appetite for Voodoo, convinced that they had tasted the real thing.
Haitians have no word for religion. Religion, as we know it, permeates life; therefore, there is no reason to separate it out. In fact, if you somehow managed to ask the right question, a Haitian peasant would probably say, "I'm Catholic." If he/she trusted you, would add, "and I serve the lwa (spirits)." You have to be Catholic to serve the spirits, but not vice versa. Some claim to be "only Catholics."
Of course, the Catholic church admonishes people not to practice anything else, but people ignore them. Formal Catholicism co-exists with other beliefs and practices, but the folk religion encompasses both. Hence, the name, folk religion. This encompasses a continuum of African spirits, Creole spirits, catholic saints. Most ceremonies include Catholic liturgy as well as Creole prayers derived from Africa. Some lwa and saints are visibly the same people (e.g., Ogoun and St. Patrick, or Legba and St. Peter; also, Adam and Eve are reinterpreted as the Divine Twins). Often, pilgrimage festivals in honor of the anniversaries of the saints' births are celebrated both in church (e.g. giving alms) and outside with dance and drum.
Oriented Toward Past. The ideal is to imitate forms of the past. Elders--or people with the longest "present" or knowledge of the past--are venerated. Events happen in the present, then get incorporated in the past. Essentially, there is no concept of the future.
Spirits (ancient dead) and recent ancestors are intimately involved in the lives of descendants. There exists a two-way dependency: spirits and ancestors can exert powers of life and death. They can both help and harm, bring prosperity and fertility or disease, misfortune, and death.
At the same time, spirits are also dependent upon the living. The dead and spirits are kept alive by human acts of their descendants--namely, by demonstrating respect, feeding, pouring libations, prayers. The living reproduce the dead, and in doing so, insure their place on a stool in ancestral society (which mirrors the living world). In this, ancestral "lineages" are linked to contemporary ones.
The meaning of death is both biological and cultural. Each culture has socially circumscribed definitions of living and dead states.
Death is a social fact, not merely biological reality. A person is socially dead after having passed through a rite of passage, such as a funeral and burial. This process may last years. In the black Caribbean, there is a novena after funeral and burial. There is then a secondary rite one year or more after death to take the spirit and put it in a clay vessel inside the ancestral shrine (containment). There the spirit is then contained/controlled, and ritual specialists who speak the sacred language of the spirits can summon them there and make them "talk." This is important in future practices of divination, when spirits make their wishes known.
Ritual is the means by which beliefs and myths are enacted, where ancient spirits manifest themselves through possession. They create an intimate and immediate relationship between person and god. One can communicate with spirits "in person." The process requires full, emotional, and energetic participation. It is not restrained or cerebral. There is no distinction between active performer and passive audience. Everyone actively participates.
People coerce and invoke spirits to intervene on their behalf or to appease them to leave them alone. Often, this includes call and response (antiphony), or more generally, the give and take between groups. There is much emphasis on percussion.
In Possession, a person's personality goes out, and that of the spirit enters. Often, this is symbolized by a horse and rider (wherein the spirit rides the horse). In possession, a god inhabits your body to make contact with you and the community.
It is difficult to understand possession from a Western perspective. Westerners often interpret possession as a form of mental disturbance, or schizophrenia. In the western, modern world, we conceive of the person as a single, distinct being who operates on one level of consciousness, at least when one is oneself. The African and Afro-American view is opposite: at the center each person are many beings.
Spirits are full, rich character types. They are not clearly good or evil. They contain symbols of certain aspects of life in all of its contradictions. In other words, they mirror life; they are images that teach you how to see the world. Spirits, like children, can be capricious, jealous, kind, envious, etc. The Christian idea of sin doesn't apply. There is no need for a savior, especially a savior whose main purpose is to save one from oneself. Forces that threaten man are out there in the world: the forces of nature and of the gods (Karen Brown). It gives you a range of choices of how to be in the world.
The African creator god created twin progenitors, Mawu and Lisa. They ordered the world. Their twinness is an important principle. It is a symbol of complementarity and interdependence. It serves as a model for gender relations. This contrasts with the Judeo-Christian belief of God as Father and Father as Divine.
Magic includes the premise that rather than being within you, forces are flowing all around, and they can inhabit and affect you. Gods make you sick by "grabbing" you. Sorcerers can poison or "fix" you. Culturally, spirits are treated very pragmatically; they are well-known and accepted forces of society. People have recourse to magic, and they use it all the time for help and harm, for fertility, crops, business, protection, etc.
Hence, "medicine" translates as a preparation, a remedy, a charm that can be used in a variety of contexts that may have nothing to do with the health of the body. Magic is an informal system. There is no hierarchy of clergy, nor any written theology. There is tremendous variation from region to region and from village to village.