Jmj
Brian_C, I don’t actually know if it is prohibited for a faithful Catholic to take part in a Protestant “communion.” But, why do Protestants call their “Lord’s Supper” service “communion?” Who or what are they in communion with? You use an example of a service where there are no implied allegiances or union… what kind of service would that be? Even the Baptist services I go to call it “communion” – should they drop the use of the word “communion” and just call it “The Lord’s Supper” to keep their integrity in check then? It’s all very interesting… to be sure!
For Catholics, the Eucharist (Communion) is the most important thing we can participate in! There is no equivalent in Protestantism, so I can see how it would be difficult for a Protestant to relate. I wonder, at the more frequent Baptist service I attend, what would be the “source and summit” part? Is it during the awesome light show when the church band rocks out for several songs up on the stage? The Bible study led by their Pastor (which are actually pretty good… usually 90% or more heresy free!) where we all flip back and forth in our Bibles? Or the part when somebody gets on stage, grabs a microphone, closes their eyes, and “wings” a 15 minute prayer (that are usually very nice for being completely off the cuff!) while the collection baskets go around? Sometimes when I attend a Protestant service they say things like, “It’s so awesome to be here to worship Jesus Christ, who is right here with us!” – I always look around for the tabernacle and wonder: “Where!?”

There is definitely an order to it… not liturgical, but a loose order nonetheless. But, I would have to guess that the high point is at the end of the Pastor’s Bible study when he wraps it up by making his point… sort of like Jerry Springer’s “Final Thought” time at the end of his show.
If it’s prohibited, I think that it could possibly be because Protestants have lost the true meaning for “communion” and Catholics should be aware of how serious a thing that is. If it’s not, I would (personally) recommend that individual Catholics exercise caution about sending the wrong message… taking communion at a Protestant church could leave Protestants with the wrong impression… like their version of communion is the same or just as “good” as the Church’s.
The Catechism states: “
Ecclesial communities derived from the Reformation and separated from the Catholic Church, ‘have not preserved the proper reality of the Eucharistic mystery in its fullness, especially because of the absence of the sacrament of Holy Orders.’ It is for this reason that, for the Catholic Church, Eucharistic intercommunion with these communities is not possible.” CCC 1400 Now, that doesn’t say explicitly that Catholics should not participate in Protestant “communion” services… but immediately proceeding this, the Catechism talks about sharing in the Eucharist with the Eastern churches… and that it is “
not merely possible but is encouraged.” So, the Church seems to state (rather clearly I think) that under certain circumstances - taking Communion with Orthodox Christians is acceptable… but it gives no such indication that doing so with Protestants is acceptable. I think the silence here may be deafening… but that’s purely speculation! I’m just an un-educated layman!
Protestants can do all kinds of great things in their services! I’ve been to some VERY enthusiastic churches, where the love of our Lord among the people is visually and audibly obvious! They can be a lot of fun! And I have learned a lot from some very knowledgeable Protestant ministers and theologians – no doubt. I’m not sure what you were suggesting about “why a Catholic should be allowed to participate in any aspect of a protestant service” – but, I can tell you this… I have enjoyed the company of and have learned from many Protestants! Our separated brothers and sisters do have some good things to share and teach an individual Catholic! However, it does seem a shame that they “insist upon one thing not commanded by Christ, and neglect most of the things insisted upon by Him.”
May the Lord be with you!
Jason