The ritual of baptism traces back to John the Baptist, who used the waters of the Jordan River to symbolize the washing away of old, limited beliefs that would make room in consciousness for a new understanding of our relationship to the power of God. Jesus was baptized by John, but there is no indication that he ever used the ritual himself.
Early Christians came to this new belief system after lives spent accepting and proclaiming other beliefs. Baptism thus became an important symbol of their willingness to leave the past behind—not just old beliefs, but entire ways of life—and follow the guidance and message of the Christ. With both John and the early Christians, those baptized were adults, and what were washed away were the beliefs of their pre-Christian lives.
The baptism of babies came later, after church fathers—chiefly Iraneus and Augustine—developed the idea of original sin. This belief holds that we "inherit" the sin of Adam and Eve simply by being born into human form—and that sin must be washed away before we begin the process of atonement that life requires.
Unity does not believe in the idea of original sin. We do not believe that babies are inherently sinful or that this life experience is intended as punishment. We see each baby as a perfect expression of the Christ—the Allness of God in fresh human form. Like all of us, their consciousness becomes clouded by the shadows and illusions of this human experience; but at birth they radiate an infinite and pure spiritual energy.
So we do not baptize in the traditional Christian sense of washing away original sin. Our christening ceremony does not wash away sin. It rather acknowledges and appreciates that a perfect spiritual being is joining us in this human dimension, honors and supports those who will be guiding him or her through mortal challenges, bestows the name by which the child will be known, and offers the support of the entire spiritual community as his or her life unfolds.