Babalu-Aye is an orisha of the Yoruba tradition and of the African-diaspora religions of Cuba and Brazil, the deity of disease and of its healing, associated above all with smallpox and other epidemics and with afflictions of the skin. He holds together, as many powerful spirits do, the two faces of the force he governs: he is feared as the bringer of pestilence, the one who can send the epidemic through a community, and he is revered as the one who can withhold or cure it, the great healer to whom the sick turn. This double character means he is approached with deep respect and even with a kind of awe; among the Yoruba he is often not named directly but addressed by praise-names and honorifics such as "father, lord of the earth," out of reverence for his power and reluctance to call the disease itself by name. He is imagined as an elder, his body marked by the pox and by sores, moving with the aid of crutches or a staff, covered in a garment of raffia palm fibre that veils and contains his power, and accompanied by dogs, which lick his wounds.
In the diaspora religions his worship is especially strong: in Cuban Lucumi (Santeria) he is honoured as San Lazaro, associated with the poor, sore-covered Lazarus of the Catholic tradition, and his feast in mid-December draws enormous popular devotion, with the sick and those who have made vows coming to give thanks for healing. These are living religions of great vitality, and Babalu-Aye is among their most important and most fervently served spirits, the orisha of the epidemic and of its cure, feared, revered, and turned to in sickness with hope of healing.