2 Bible Verses about Books, Metaphorical Use

Then I saw a great white throne, and him that sat on it, from whose presence the earth and the heaven fled away, so that they disappear'd. and I saw the dead, small and great, stand before the throne; the books were opened: and another book was opened, which is the book of life: and the dead were judged out. of those things which were written in the books, according to their works.

so I went to the angel, and said to him, "give me the little book." and he said to me, "take it, and eat it up; it shall prove bitter in thy bowels, but in thy mouth it shall be as sweet as honey." immediately having took the little book out of the angel's hand, I swallowed it down: and in my mouth it was as sweet as honey: but as soon as I had swallowed it, it was bitter within me.