You've likely landed on this page because you are Catholic and struggling with saying "consubstantial" in place of "one in Being" at Mass. The new translation of the Nicene Creed in the Roman Missal is now more precise — but it is a bit harder to get your head around it, isn't it?

Well, we are here to help you understand.

"Consubstantial" is an unusual word ("consubstantialem" in the Latin text) that will require some catechesis, but it is a crucial early theological term, asserting that the Son is of the “same substance” with the Father – meaning He equally shares the Father’s divinity as a Person of the Holy Trinity. Although it carries the same basic meaning as “one in being,” the more precise use of “consubstantial” is an acknowledgement of how the Greek equivalent of the word was so important for safeguarding orthodoxy in the early Church. In the Fourth Century, the description “homoousios” (“same substance”) was affirmed over “homoiousios” (“like substance”). The reality of who Christ is thus hinged upon a single letter!

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