2. a public ceremony in which a new ship is formally named and launched.
3. an act or instance of naming or dedicating something new.
Christening is the old name for Baptism. Usually Christening refers to the name given to the infant or person during baptising. When babies are baptised, their parents promise to help them grow up as Christians. Water is poured on the baby to symbolise a fresh start with God. Also, the purpose of a christening (or the more modern term, baptism) is providing a symbol that you want to bring your child up in the eyes of God, and will try to provide them with Christian beliefs to the best of your abilities. The water represents a fresh start after having been cleansed from original sin.
Traditionally, Christening was the naming ceremony to give the child a Christian name. It was usually done at the same time as baptism, so the two got intertwined. During the baptism ceremony, parents are asked what name they have given their child.
Baptism brings a child into the Christian family. For Catholics, it is the sacrament where a person is, thanks to Jesus, washed clean from original sin. It is the first of our three sacraments of initiation (the other two being Confirmation and Eucharist).
The form of baptism is: "I baptize you in the name of the Father, and of the Son, and of the Holy Ghost." or
"I baptize you in the name of the Father, and of the Son, and of the Holy Spirit."
If there is some doubt about the validity of your baptism, the conditional form of baptism is: "If you are baptised, I do not baptize you again, but if you are not yet baptised [pour water on the head, making sure it touches the skin] I baptize you in the name of the Father, and of the Son, and of the Holy Ghost." In lack of Catholic priests, you can have a Catholic friend perform a conditional baptism, and you can administer baptism to your own children.
Pope Eugene IV, Council of Florence, "Exultate Deo," 1439: "In case of necessity, however, not only a priest or a deacon, but even a layman or woman, yes even a pagan and a heretic can baptize, so long as he preserves the form of the Church and has the intention of doing what the Church does." (Denz. 696)
Baptism is the sacrament of faith. But faith needs the community of believers. It is only within the faith of the Church that each of the faithful can believe. The faith for Baptism is not a perfect and mature faith, but a beginning that is called to develop. The catechumen or the godparent is asked: "What do you ask of God's Church?" The response is: Faith.
The sign of the cross, on the threshold of the celebration, marks with the imprint of Christ the one who is going to belong to him and signifies the grace of the redemption Christ won for us by his cross. Since Baptism signifies liberation from sin and from its instigator the devil, one or more exorcisms are pronounced over the candidate. The celebrant then anoints him with the oil of catechumens, or lays his hands on him, and he explicitly renounces Satan. Thus prepared, he is able to confess the faith of the Church, to which he will be entrusted by Baptism.
The baptismal water is consecrated by a prayer of epiclesis (either at this moment or at the Easter Vigil). The Church asks God that through his Son the power of the Holy Spirit may be sent upon the water, so that those who will be baptised in it may be "born of water and the Spirit." It signifies and actually brings about death to sin and entry into the life of the Most Holy Trinity through configuration to the Paschal mystery of Christ. The use of water as a purifying substance is universal. Water is also symbolic of the beginnings of life, and human life which emerges from the waters of the womb.
The anointing with sacred chrism, perfumed oil (olive oil mixed and perfumed with other precious oils) consecrated by the bishop, signifies the gift of the Holy Spirit to the newly baptised, who has become a Christian, that is, one "anointed" by the Holy Spirit, incorporated into Christ who is anointed priest, prophet and king.
The white garment symbolizes that the person baptised has "put on Christ," has risen with Christ.
The candle, lit from the Easter candle signifies that Christ has enlightened the neophyte. In him the baptised are "the light of the world."
The solemn blessing concludes the celebration of Baptism. At the Baptism of newborns the blessing of the mother occupies a special place.