For many centuries tribal masks played a major role in rituals, celebrations, ceremonial and tribal initiations. Masking rituals are normally accompanied with prayer, music, song and/or dance. Before starting to sculpt, the artisan will purify himself and perform a prayer, consulting the divine forces and spirits of his ancestors for guidance. During the sculpting process, the divine force is transferred to the mask and the carver offers a sacrifice to the spirit of the tree. Some masks are used to ward off evil spirits and some are used to celebrate.