The original meaning of the term canon can be traced to the ancient Greeks, who used it in a literal sense: a kanon was a rod, ruler, staff, or measuring rod. . . . This literal concept provided the basis for a later extended use of the word kanon, meaning standard, norm. Galatians Gal. 6:16 comes closest to the final theological significance of the word, as Paul says Those who will walk by this rule [kanon], peace and mercy be upon them. . . . From the literal ruler, the word was extended to mean a rule or standard for anything. In early Christian usage, it came to mean rule of faith, normative writings, or authoritative Scripture.1 While the canon of scripture means the list of books accepted as holy scripture, the other sense of canonrule or standardhas rubbed off on this one, so that the canon of scripture is understood to be the list of books which are acknowledged to be, in a unique sense, the rule of belief and practice.2
1 Norman L. Geisler and William E. Nix, A General Introduction to the Bible (Chicago, IL: Moody Press, 1986), 203-204.
2 F. F. Bruce, The Canon of Scripture (Downers Grove, IL: Intervarsity Press, 1988), 18.