The following is an excerpt from the Introduction to Understanding the Four Views on Baptism by John. H Armstrong explaining the importance of baptism in the early church.
“Baptism” derives from the Greek word baptisma and denotes the action of washing or plunging in water (Acts 2:41). From the earliest days of Christianity baptism has been a rite of initiation . . . Christians have always baptized as a sign of their allegiance to Jesus Christ. . . . Though the meaning and mode of baptism remain controversial, the simple fact is that the reality itself remains profoundly important. This underscores another important point often missed by modern believers, namely, the relationship between the symbol and ritual. Early Christians, living in a premodern context, had little problem understanding how symbol and reality were intimately connected. They would never have spoken the way many of us do when we refer to baptism as a “mere” symbol. For them symbols and rituals, when authorized by Jesus and practiced by his devout followers because of his commands, were effective and power-laden signs. The emphasis of the early church was never opposed to ritual so much as it was committed to helping people understand (via discipleship) the various Christian rituals (which were simple and few) in their proper context. By catechism and liturgical practice the earliest Christians sought to continually underscore the importance of symbol for obedience to Jesus.”
Baptism is the washing with water in the name of the Father, the Son, and the Holy Spirit; it signifies and seals our adoption into Christ, our cleansing from sin, and our commitment to belong to the Lord and to his church.