Mark 4:22 - Ellicott's Commentary On The Whole Bible

For there is nothing hid. — This also is found elsewhere (e.g., in Matthew 10:26). The Greek word here for “secret” is interesting as being the same as that which we find in our word “Apocrypha.” The term was, in the first instance, applied to books that were surrounded with the secrecy of a spurious sacred-ness, but were not publicly recognised in the Church as being of divine authority, and was then transferred to all books which, whether “spurious” or “secret,” wanted that recognition.