Q: May non-Catholics do scripture readings and take up the gifts at a Catholic wedding mass?
A: For readers, the Directory for the Application of Principles and Norms on Ecumenism says this: “The reading of Scripture during a Eucharistic celebration in the Catholic Church is to be done by members of that Church. On exceptional occasions and for a just cause, the Bishop of the diocese may permit a member of another Church or ecclesial Community to take on the task of reader” (133).
GIRM 73 says, “It is a praiseworthy practice for the bread and wine to be presented by the faithful.”
Thus, it’s possible for non-Catholics to read at a wedding if the bishop permits it, and for them to carry up the gifts – but it makes more sense if the people bringing up the gifts are also going to be receiving communion from them once they have been consecrated.
Non-Catholics could read petitions, but it makes more sense if they have been baptized because that is the prayer “of the faithful.”