Believer's Baptism :

Baptism, commonly referred to as believer's baptism among Baptists, is a "sacrament" or "ordinance" of the church that according to Baptist doctrine plays no role in salvation, being properly performed only after salvation, and is performed after a person professes Jesus Christ as Lord and Savior. It is seen as an act of obedience to the example and command of Jesus given in the Great Commission Matthew 28-19-20. It is an outward expression that is symbolic of the inward cleansing or remission of their sins that has already taken place. It is also a public identification of that person with Christianity and with that particular local church. Most Baptist churches consider baptism by full immersion, subsequent to salvation, a criterion for church membership. Thus, most churches reject:prior baptisms by any means other than immersion baptisms performed as an infant or child too young to make a personal decision to accept Christ baptisms performed by any means, including immersion, if administered by a church not considered to be of "like faith and order" by the Baptist congregation. There are some groups that call themselves "Christians," baptize beyond infancy by immersion, that would not be considered "Christian" according to Baptist understanding of the word
Through Anabaptist influence, Baptists reject the practice of pedobaptism or infant baptism because they believe parents cannot make a decision of salvation for an infant. Related to this doctrine is the disputed concept of an "age of accountability" when God determines that a mentally capable person is accountable for their sins and eligible for baptism. This is not necessarily a specific age, but is based on whether or not the person is mentally capable of knowing right from wrong. Thus, a person with severe mental retardation may never reach this age, and therefore would not be held accountable for sins. The book of Isaiah mentions an age at which a child "shall know to refuse the evil, and choose the good" but does not specify what that age is. It is important to note that the doctrine of original sin, accepted by some Baptist churches, negates the "age of accountability" as all were born into sin. However, even these churches believe that infants and young children will still be covered by Christ's atoning blood, should they die.

Baptists insist upon baptism by full immersion, the mode presumed to have been used by John the Baptist. This consists of lowering the candidate in water backwards while the baptizer (a pastor or any baptized believer) invokes the Trinitarian formula of Matthew 28:19 or other words concerning a profession of faith. This mode is also preferred for its parallel imagery to the death, burial, and resurrection of Jesus.

Recognition of baptisms by other modes and Christian groups vary. Most Baptist churches only recognize baptism by full immersion as being valid. Exceptions are sometimes made to baptize by sprinkling as a practical alternative for the disabled or elderly or in times of drought. Some Baptist churches will recognize adult baptisms by immersion performed in other Christian churches of "like faith and order," while others only recognize baptisms performed in Baptist churches. In very rare instances, a church may recognize only its own baptisms as valid.