Steve Ray has a list of 35 loaded Questions for "Bible Christians" (quotation marks his)(link to the whole list). This is number 3/35. I'm trying to provide the answers in a common format, for easy reference.
3) Where in the New Testament do the apostles tell future generations that the Christian faith will be based solely on a book?
Nowhere that we know of.
1) But all of the apostles' instructions that we know of, we know of from a book.
2) And the apostles did instruct us that the scriptures are sufficient to serve in the role in question:
2 Timothy 3:16-17
All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness: that the man of God may be perfect, throughly furnished unto all good works.