It is a little difficult to understand. Ill try to explain it and I hope I dont state anything that is not correct but as I understand it, as long as it is a valid baptism, done with water, in the name of the father, son, and spirit and as long as the intent of the pastor baptizing is to do what the Church does, baptize into the body of Christ, the baptism is valid even if it is seen as symbolic by the person who is being baptized. The sacrament is an objective one; it is incorporating one into the invisible body of Christ. Whether a pastor and a baptizeie sees this as a merely symbolic joining, they intend to be joined to the church (the mystical body of Christ through their baptism.