Proverbs 22:20,21 Have not I written to thee excellent things in counsels and knowledge, That I might make thee know the certainty of the words of truth; that thou mightest answer the words of truth to them that send unto thee? The Lord has written the words of truth so that we can have absolute certainty about them. Textual critics are wasting their time trying to find what God promised to preserve. They believe the Scriptures were inspired of God, but they don't believe God preserved every word intact. If God's inspired Word has not been super-naturally preserved, then we don't have God's inspired Word today. Thank God we don't have to guess whether or not He preserved His Word, He has promised it in many many verses! Luke 21:33 Heaven and earth shall pass away: but my words shall not pass away. Amen!