From a biblical perspective, Christian initiation “orders” or, if you prefer, “configures” the believer to Christ within the community of faith, Christ’s body. Christian initiation does not just make one a different kind of individual, it draws the believer into a profound ecclesial relationship, one’s ecclesial ordo within the life of the church. The distinctive character of this baptismally ordered relationship unfolds in three dimensions. Vertically, if you will, we are baptized into communion with God, in Christ, by the power of the Spirit. Yet this relation is inseparable from our horizontal relationship with all our brothers and sisters in baptism who constitute together a communion of believers. These two dimensions of the baptismal ordering must, in turn, be conjoined to a third dimension, the movement outward toward the world in mission. This three-dimensional ecclesial relation established by Christian initiation offers us our primal identity as Christian believers and it can never be abandoned. It constitutes the very essence of Christian discipleship.
Richard R. Gaillardetz, An Unfinished Council: Vatican II, Pope Francis, and the Renewal of Catholicism (Collegeville, MN: Liturgical Press, 2015), p. 138. ISBN: 978-0-8146-8309-5.