From the CCC:
1227 According to the Apostle Paul, the believer enters through Baptism into communion with Christ's death, is buried with him, and rises with him:- Do you not know that all of us who have been baptized into Christ Jesus were baptized into his death? We were buried therefore with him by baptism into death, so that as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.29
As to the necessity for growing in grace, that is, sanctifying grace, the sacrament of Baptism opens the door to such a journey.
III. HOW IS THE SACRAMENT OF BAPTISM CELEBRATED?
Christian Initiation
1229 From the time of the apostles, becoming a Christian has been accomplished by a journey and initiation in several stages. This journey can be covered rapidly or slowly, but certain essential elements will always have to be present: proclamation of the Word, acceptance of the Gospel entailing conversion, profession of faith, Baptism itself, the outpouring of the Holy Spirit, and admission to Eucharistic communion.
And, I skip to here...
The Baptism of infants
1250 Born with a fallen human nature and tainted by original sin, children also have need of the new birth in Baptism to be freed from the power of darkness and brought into the realm of the freedom of the children of God, to which all men are called.50 The sheer gratuitousness of the grace of salvation is particularly manifest in infant Baptism. The Church and the parents would deny a child the priceless grace of becoming a child of God were they not to confer Baptism shortly after birth.51
1251 Christian parents will recognize that this practice also accords with their role as nurturers of the life that God has entrusted to them.52
1252 The practice of infant Baptism is an immemorial tradition of the Church. There is explicit testimony to this practice from the second century on, and it is quite possible that, from the beginning of the apostolic preaching, when whole "households" received baptism, infants may also have been baptized.53
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1251 Christian parents will recognize that this practice also accords with their role as nurturers of the life that God has entrusted to them.52
1252 The practice of infant Baptism is an immemorial tradition of the Church. There is explicit testimony to this practice from the second century on, and it is quite possible that, from the beginning of the apostolic preaching, when whole "households" received baptism, infants may also have been baptized.53
Faith and Baptism
1253 Baptism is the sacrament of faith.54 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 required 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!"
1254 For all the baptized, children or adults, faith must grow after Baptism. For this reason the Church celebrates each year at the Easter Vigil the renewal of baptismal promises. Preparation for Baptism leads only to the threshold of new life. Baptism is the source of that new life in Christ from which the entire Christian life springs forth.
1255 For the grace of Baptism to unfold, the parents' help is important. So too is the role of the godfather and godmother, who must be firm believers, able and ready to help the newly baptized - child or adult on the road of Christian life.55 Their task is a truly ecclesial function (officium).56 The whole ecclesial community bears some responsibility for the development and safeguarding of the grace given at Baptism.
Remember, that whenever the CCC uses the term "divine life", the teachers mean sanctifying grace, the Life of God in us. And, here is more clarification: and there is more here:
1266 The Most Holy Trinity gives the baptized sanctifying grace, the grace of justification:
- enabling them to believe in God, to hope in him, and to love him through the theological virtues;
- giving them the power to live and act under the prompting of the Holy Spirit through the gifts of the Holy Spirit;
- allowing them to grow in goodness through the moral virtues.
Thus the whole organism of the Christian's supernatural life has its roots in Baptism.
To be continued.....