Q: Is there any ritual book or instruction that lays out how to have baptisms at Sunday Mass? I have been at parishes that have customary ways, but I have not been able to find any documentation to back up these practices.
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A: The description is in the Rite of Baptism for Children, paragraph 29, with a little extra information in paragraph 30. This was one of the first of the revised liturgical books after Vatican II, so the information is spotty, not developed.