Q: Local Episcopal, Anglican and Methodist churches are lending musicians and choir members for a Divine Worship Mass I plan to celebrate during the Week of Prayer for Christian Unity. I would like honor them at the Mass to the full extent possible, without causing confusion to the Catholic faithful. If they should choose to wear cassock, surplice and stole or alb and stole, would that be OK? Or does risk implying that they are con-celebrants at a Catholic Mass? What do you think?
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A: I don’t see a direct answer to this in the Directory for the Application of Principles and Norms on Ecumenism. But #118 permits mutually agreed upon vesture at other services, such as non-liturgical prayer in common http://www.christianunity.va/content/unitacristiani/en/documenti/testo-in-inglese.html .
It’s 129-136 that deal with others participating in Catholic sacraments, and it is silent about dress. However, #133 says a bishop may authorize a non-Catholic minister to proclaim scripture. It seems to me that that would permit appropriate vesture then and in other parts of the service. Notice also 136—if a minister may have a role in weddings, surely that minister could vest.