This is a quote taken from John Piper's ordination message "Ministry of the Word" spoken over Steve Roy in 1984 which discussing the importance of a pastor/preacher spending personal time in study of God's Word:
Richard Baxter wrote something that could save many young pastors years of regret in misdirected study. He said, "Till at last, being by my sickness cast far from home, where I had no book but my Bible, I set to study the truth from thence, and so, by the blessing of God, discovered more in one week than I had done before in seventeen years' reading, hearing, and wrangling."
We must beware of the temptation to replace the study of Scripture with the reading of good books about the Scripture. If you want to know if a man has studied well, don't ask him to show you his library. Ask him to show you his personal notebooks where he has recorded his own authentic insights into the Word of God.