In Christianity, baptism (from Greek baptizo: "immersing", "performing ablutions", i.e., "washing")[1] is the ritual act, with the use of water, by which one is admitted to membership of the Christian Church and, in the view of some, as a member of the particular Church in which the baptism is administered.
The usual form of baptism among the earliest Christians was for the candidate (or "baptizand") to be immersed totally or partially.[2][3][4][5][6] While John the Baptist's use of a deep river for his baptism suggests immersion,[7] pictorial and archaeological evidence of Christian baptism from the 3rd century onwards indicates that the normal form was to have the candidate stand in water while water was poured over the upper body.[8][9][10][11] Other common forms of baptism now in use include pouring water three times on the forehead.
Baptism was seen as in some sense necessary for salvation, until Huldrych Zwingli in the sixteenth century denied its necessity.[12] Martyrdom was identified early in church history as baptism by blood, enabling martyrs who had not been baptized by water to be saved. Later, the Catholic Church identified a baptism of desire, by which those preparing for baptism who die before actually receiving the sacrament are considered saved.[13]
Some Christians, particularly Quakers and the Salvation Army, do not see baptism as necessary. Among those that do, differences can be found in the manner and mode of baptizing and in the understanding of the significance of the rite. Most Christians baptize "in the name of the Father, and of the Son, and of the Holy Spirit" (following the Great Commission), but some baptize in Jesus' name only. Most Christians baptize infants,[14] many others do not. Some insist on submersion or at least partial immersion of the person who is baptized, others consider that any form of washing by water is sufficient.