This document from the Vatican does imply that Catholics should refrain from Sacramental Godparenting Children from non Catholic Christian communities. It allows for witnessing the Baptism.
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Now that I know that the Church does not support me in being a Godparent to my neice, do I have regrets? Probably not. Would I do it again while knowing this teaching? I would have to look into the interpretation of this teaching a little more to say for sure. Like I said before, I do know that I would not take their Communion if I knew what I know now. And I guess I would have had a little more conversation about things with my sister.
From
this link:
Traditionally, we identify the sponsor of a child for baptism as the godparent — godmother or godfather, but the technical term (in Canon Law) remains “sponsor.”
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Strictly speaking, a person only needs one sponsor for baptism — male or female, but may have two sponsors, one male and one female.
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Technically, only Catholics can be godparents or sponsors. A Christian of another denomination, whether Orthodox or Protestant, however, may be a “Christian witness” to the baptism along with the Catholic godparent. The reason for this distinction and restriction is that the godparent not only is taking responsibility for the religious education and spiritual formation of the baptized person, but also is representing the Church, the community of faith, into which the person is being baptized. A Christian who is not Catholic, although perhaps a very holy, Christian, cannot fully attest to the beliefs of the Catholic Church. Likewise, a Catholic can only be a Christian witness for someone who is baptized into another Christian denomination.
So, basically, the difference between “sponsor” and “Christian witness” boils down to whether or not one is a member of the same Church or ecclesial community as the one in which the baptism is being performed.
My wife grew up Lutheran, as did her maid of honor. The maid of honor is a Christian witness to our older son’s baptism (my brother is the sponsor). Similarly, my wife is sponsor to her maid of honor’s adopted daughter, and I am a Christian witness. Since then, my wife completed RCIA and entered the Church… but I’m pretty sure that does not somehow “undo” the validity of her maid of honor’s adopted daughter’s Lutheran baptism!
I like the symbolism of the sponsor representing the community of faith into which a person is baptized. That said… years later, when our niece (my wife’s brother’s daughter) was baptized (also Lutheran), I was a bit surprised that *neither *of her sponsors were Lutheran. I guess other denominations don’t make that same “sponsor/Christian witness” distinction.