The quote (I think) first appeared in print in the book titled
Essential Truths of the Christian Faith, original hardback published in 1992, the Amazon softback edition 1998. I used to have the page number memorized too (I think page 22
), but would have to look that up.
R.C. Sproul also stated such in his earlier tape series on Catholicism when talking about the biblical canon, if I’m not mistaken.
Also later in Sproul’s chapter for the 1995 book
Sola Scriptura! The Protestant Position on the Bible edited by Don Kistler he says the same “fallible collection of infallible books” is the Protestant position, while “infallible collection of infallible books” he says is the Catholic position. I have the original 1995 edition, looks like it was republished in 1997.
So he’s said it at least three times. Twice in print, once in a tape series.
Phil P