Yes, it is very appropriate to baptize during a Sunday Mass. Baptism brings a child into the Church and the child shares in the death and resurrection of Christ. At Sunday Mass the Church is gathered to celebrate Christ’s death and resurrection. Thus baptism at a Sunday Mass is a perfect union of the two events.
Introduction to the Rite of Baptism:
To bring out the paschal character of baptism, it is recommended that the sacrament be celebrated during the Easter Vigil or on Sunday, when the Church commemorates the Lord’s resurrection. On Sunday, baptism may be celebrated even during Mass, so that the entire community may be present and the relationship between baptism and eucharist may be clearly seen…
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