The Byzantine Empire existed as a continuation of the Roman Empire in its eastern provinces, meaning that the form of these oil lamps shows strong similarities to the Roman style. Christianity was the predominant religion in the Byzantine world, and this is reflected in the decoration of the lamp, which could have been used for either domestic or ceremonial purposes. Doves were extremely important in early Christian symbolism, as this is the form which the Holy Spirit was said to have taken at the baptism of Christ.
To disocver more about Byzantine art, please visit our relevant blog post: The Byzantine Empire, Art and Christianity.