…we confess that Baptism is necessary to salvation, and that children are to be baptized, and that the baptism of children is not in vain, but is necessary and effectual to salvation.
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For it is very certain that the promise of salvation pertains also to little children [that the divine promises of grace and of the Holy Ghost belong not alone to the old, but also to children]. It does not, however, pertain to those who are outside of Christ’s Church, where there is neither Word nor Sacraments, because the kingdom of Christ exists only with the Word and Sacraments. Therefore it is necessary to baptize little children, that the promise of salvation may be applied to them, according to Christ’s command, Matt. 28:19: Baptize all nations. Just as here salvation is offered to all, so Baptism is offered to all, to men, women, children, infants. It clearly follows, therefore, that infants are to be baptized, because with Baptism salvation [the universal grace and treasure of the Gospel] is offered. 53] Secondly, it is manifest that God approves of the baptism of little children.
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That God, however, approves of the baptism of little children is shown by this, namely, that God gives the Holy Ghost to those thus baptized [to many who have been baptized in childhood]. For if this baptism would be in vain, the Holy Ghost would be given to none, none would be saved, and finally there would be no Church. [For there have been many holy men in the Church who have not been baptized otherwise.]