Huh? I think you have this backward. ... There is nothing in the Scripture whatsoever that says you must be "of age" to be baptized. Baptism is simply washing away the grime that comes from our corrupt nature, the patina that forms on out souls as it does on copper.
By "order" in scripture I meant as in the Great Commission, or the story of the eunuch (Acts 8:26-39). In both cases the belief is to come before Baptism. On the other hand, to my knowledge there is zero Biblical support for infant sprinkling as saving Baptism.
FK: "... is there such a thing as "initial theosis", or are these ideas not really comparable?"
There is such a thing but it has nothing to do with baptism. Initial theosis would be the beginning of a life in Christ.
Since Catholics believe that Baptism is initial salvation, is this a source of disagreement you have with them? What does Baptism mean to you?
FK, in Orthodoxy, Baptism is always followed by Chrismation so the sacraments should be looked at together. Here's what the GOA website says:
"BAPTISM
The Sacrament of Baptism incorporates us into the Church, the Body of Christ, and is our introduction to the life of the Holy Trinity. Water is a natural symbol of cleansing and newness of life. Through the three-fold immersion in the waters of Baptism in the Name of the Holy Trinity, one dies to the old ways of sin and is born to a new life in Christ. Baptism is one's public identification with Christ Death and victorious Resurrection. Following the custom of the early Church, Orthodoxy encourages the baptism of infants. The Church believes that the Sacrament is bearing witness to the action of God who chooses a child to be an important member of His people. From the day of their baptism, children are expected to mature in the life of the Spirit, through their family and the Church. The Baptism of adults is practiced when there was no previous baptism in the name of the Holy Trinity.
CHRISMATION
The Sacrament of Chrismation (Confirmation) immediately follows baptism and is never delayed until a later age. As the ministry of Christ was enlivened by the Spirit, and the preaching of the Apostles strengthened by the Spirit, so is the life of each Orthodox Christian sanctified by the Holy Spirit. Chrismation, which is often referred to as one's personal Pentecost, is the Sacrament which imparts the Spirit in a special way.
In the Sacrament of Chrismation, the priest anoints the various parts of the body of the newly-baptized with Holy Oil saying: "The seal of the gifts of the Holy Spirit." The Holy Oil, which is blessed by the bishop, is a sign of consecration and strength. The Sacrament emphasizes the truths that not only is each person a valuable member of the Church, but also each one is blessed by the Spirit with certain gifts and talents. The anointing also reminds us that our bodies are valuable and are involved in the process of salvation.
The Sacraments of initiation always are concluded with the distribution of Holy Communion to the newly-baptized. Ideally, this takes place within the celebration of the Divine Liturgy. This practice reveals that Orthodoxy views children from their infancy as important members of the Church. There is never time when the young are not part of God's people."