RCIA is the Rite of Christian Initiation of Adults. It’s the process through which adults come into the church. This site will give you an overview of the process: ecatholic2000.com/rcia/rcia.shtml
It is a Ritual/Liturgical process nearly as old as the Church (2000 years) by which a person seeks to become a Christian by receiving the Sacraments of Baptism, Confirmation and Holy Communion.
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