What then does it mean to call the Bible “the Word of God”? It is important to emphasize that the Christian tradition throughout its history has spoken of the Bible as the Word of God (capital W and singular), not as the words of God (lowercase w and plural). If it had used the latter phrase, then one might reasonably claim that believing the words of the Bible to be God’s words is intrinsic to being Christian.
But the use of a capital W and the singular suggests a different meaning. Namely, “Word” is being used in a metaphorical and nonliteral sense. As with metaphors generally, this one resonates with more than one nuance of meaning. A word is a means of communication, involving both speaking and hearing. A word is a means of disclosure; we disclose or reveal ourselves through words. Words bridge the distance between ourselves and others: we commune and become intimate through words.
To call the Bible the Word of God is to see it in all of these ways, and no doubt more. The Bible is a means of divine self-disclosure. The traditional theological phrase for this is “the Bible as the revelation of God.”
If I have any quibble with Borg here, it is that I prefer to reserve the capital W for references to Jesus as the Word of God.
Marcus Borg, Reading the Bible Again for the First Time: Taking the Bible Seriously but not Literally, 2001, HarperOne, NY. Quote is taken from pages33-4 of the Harper Collins first paperback edition, 2002