People burn sage due to a belief that the herb cleanses a living area of unwanted energies. This practice has been adopted from traditional religious rites, such as those performed by Native American tribes. Often the ritual of burning sage is referred to as smudging, and bundles of dried herbs, predominantly sage, are known as smudge sticks. Burning sage releases a thick, gray smoke and has a sweet, aromatic scent.
In some Native American ceremonies, sage was burned to keep pipes and other sacred objects free of negative energies. The smoke was also used for purification purposes, and to bless people. Traditionally, white sage was considered to be a spiritual medicine, and care was taken to gather the herb at specific times of the year or phases of the moon.
Religious and spiritual ceremonies in many cultures involve the use of scented smoke for purposes of purification and healing. For instance, the ritual of burning sage is common amongst those who practice witchcraft. This removal of lingering energies, including evil spirits, is referred to as "casting a circle."
Other forms of New Age and Neopagan spiritual practices have also adopted the practice of smudging. However, some members of Native American cultures have protested modern smudging as false imitation and cultural appropriation.