841 The Church's relationship with the Muslims. "The plan of salvation also includes those who acknowledge the Creator, in the first place amongst whom are the Muslims; these profess to hold the faith of Abraham, and together with us they adore the one, merciful God, mankind's judge on the last day."
I understand this to mean that anyone who, through invincible ignorance (no fault of their own), does not know that the fullness of truth and life subsists in the Catholic Church, will be judged on the dictates of their conscience, as it corresponds to the portion of truth they do know.
In the case of Muslims, that includes the faith of Abraham and much of the Old Testament as well as Jesus' Virgin Birth.
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