One needs to define"Christian"
One can be a professing "Christian " ...That is intellectually accepting the creeds of the church ... or one could consider themselves a Christian because they were baptized...or because they were raised in the church ... But the question is are they relying on Christ alone for their salvation ...not their own morality, or membership in a certain church, .... Christ alone ... Christ alone..
The correct phrasing is redefine terms to match the non-Catholic view.