Aspersion is a method used in baptism as an alternative to immersion or affusion. Anglicans baptize by immersion or affusion. The word "affusion" comes from the Latin "affusio", meaning "to pour on". Baptism by immersion is not necessary; affusion and aspersion are acceptable modes. However, when a person could not be immersed, baptism by aspersion or affusion was performed. Affusion and aspersion tend to be practiced by Christian denominations that also practice infant baptism. Baptism is by immersion, or by affusion if immersion is not practical. The Roman Catholic Church primarily baptizes with affusion but occasionally does so with immersion. But in that verse of Luke, the "washing" referred to is partial, like affusion. Many Anglicans and Lutherans baptize by affusion, whereas Presbyterians and Congregationalists typically baptize with aspersion. The Catholic Church also practices infant baptism, usually by affusion, and utilizing the Trinitarian formula.