I’ve been reading his works recently—I’d heard of him before but never read him until now—and came across this great piece.
“What the People Actually Believe
“First, it seems to me that the difference between what the church officially teaches and what the people actually believe does not have a merely negative value, but a theologically positive aspect as well. The fact that the index systematicus of Denzinger can rarely be found in the heads of ordinary Christians is not as deplorable as it may seem to many people who are tempted to identify saving faith with theological formation.
“Sophisticated knowledge of something may even be a great obstacle to its personal assimilation. I suspect that today’s catechisms, however modern they claim to be, still contain too many things and that they do not present the heart of the Christian message, that which must by all means be said in a striking, really intelligible way. Moreover, it is faith in the church which actually exists in heads and hearts, and not properly official church doctrine, that immediately and in itself is the faith that constitutes the church.” (pp. 501-502)
Karl Rahner, S.J. (1992) The Content of Faith: The Best of Karl Rahner’s Theological Writings. New York: The Crossroad Publishing Company