The spiritual aspect of Shona music is so central to any presentation of mbira music that it deserves a primary place and appropriate depth of information. However as an ex-anthropologist I am hesitant to attempt to present something as complex as the world of Shona spirituality and religious beliefs and practices in a few paragraphs; and not being Shona it is almost impossible to get even the basic outlines close to accurate. However, because of the importance of the spiritual in the lives and music of the Shona people, we hope to at least point you in the right direction, quoting liberally from Solomon Murungu's web site www.zambuko.com.
The first thing that is said about mbira is that it is though mbira at bira ceremonies that the living communicate with the spirits of deceased ancestors and tribal guardians. At these ceremonies, vadzimu, give guidance on family and community matters and exert power over weather and health.
Vadzimu are ancestor spirits. and represent all that is ideal and moral about a Shona way of life and are usually associated with recent ancestors or with more remote culture heroes whose exact genealogy has been forgotten. They serve to protect society, but may withdraw this protection if Shona moral ideals are not respected.Art & Life in Africa — www.uiowa.edu/~africart
It is best to put these "facts" in some context. Here Solomon presents an introduction to Shona beliefs
Shona people believe that death is the passage of the body from one physical form to another and a separation of spirit from the body to a higher world of living spirits. Ancestral spirits are a source of comfort as well as the cornerstone of religious activity for, the living believe they are protected from worldly harm by their these spirits. Should a sudden misfortune befall a family, they turn first to their ancestral spirits for advice, guidance and protection. In many cases a family has a special spirit, or Mudzimu which, when properly appeased, speaks directly to the family through a living spirit medium. In a lengthy and protocol intensive special ceremony, called Bira or spirit possession ceremony, special songs, selected from a vast repertoire of spiritual arrangements, are recalled to welcome a deceased person's spirit back into the family. Shona prayers, poetry and words of praise are recited.Solomon Murungu — www.zambuko.com
It is in this context that mbira is played—not simply as music but as a means of communicating with the spirits. Although the mbira is the understood medium for calling the spirits, the spirits only join the bira ceremony if the mbira music so moves them. So it takes skill and endurance and a knowledge of the songs the spirits like for an mbira player to successfully call a spirit to possess a spirit medium.
It is during such a ceremony that ancestral spirits listen to the concerns of their living family members as well as impart to them the wisdom, advice, forgotten family customs and protocol to ensure a healthy and successful family or community. This is the most important religious and spiritual function of the instrument in the Shona culture and tradition.Solomon Murungu — www.zambuko.com
Mbira is performed at many different ceremonies, including rain-making ceremonies, weddings, working parties, ceremonies for appeasing of the ancestral spirits, ceremonies for installing new chiefs, and death ceremonies, including the guva ceremony in which a departed person's spirit is welcomed back into the community a year after their death.
Outside of Zimbabwe the mbira often becomes just a musical instrument, but, as Solomon Murungu points out, the instrument's components embody many spiritual aspects.
The metal keys are made from smelted iron ore which is dug out from sacred hills and holy mountains where the Shona chiefs and Shona statesmen are buried. The keys thus personify the presence of ancestral spirits directly on the instrument. The sound board, made from a special kind of tree, mubvamaropa, represents a source of shelter and fuel, basic necessities in everyday Shona life. The resonator gourd or deze, into which the mbira is mounted and propped as a second level amplifier is a special type of dried squash, called Nhangatanga or the first squash, which is a source of food. It is also used as a water container, dende. In its smaller form and dried, the nhangatanga squash is used as a drinking gourd, mukombe. The instrument thus symbolizes the basic elements of everyday life in Shona. The mbira player adds the final and human dimension to complete a Shona social institution.Solomon Murungu — www.zambuko.com