Do we need the original languages?

I'm re-reading some portions of John Piper's Brothers, We Are Not Professionals. It's a solid assault on the professionalization of the pastoral office, one that I'm sure I will turn to again and again to beat back the temptations that seek to turn the ministry into mere management.

Of note today was Piper's chapter, "Brothers, Bitzer Was a Banker." In it, Piper makes a plea for pastors to become well-versed in the original languages of Scripture- Greek and Hebrew. He tells of a man named Heinrich Bitzer, who was ardently committed to knowing the original languages of the Bible. And the kicker was this: Bitzer was a banker. Not a pastor. Not an Old Testament professor. A banker. How much more, Piper contends, should pastors be committed to Greek and Hebrew, seeing as it is the nature of their office to expound the Word of God with accuracy and power!

Piper goes on, then, to show some of the reasons pastors need to know the original languages. I thought it perhaps helpful to give them here...

1. Without the original languages, "the confidence of pastors to determine the precise meaning of the Biblical text diminishes" (82).
2. "...the uncertainty of having to depend on differing translations- which always involve much interpretations- will tend to discourage careful textual analysis in sermon preparation" (82).
3. As a result of all of this, "[expository] preaching...falls into disuse and disfavor" (83).
4. "Another result when pastors do not study the Bible in Greek and Hebrew is that they, and their churches with them, tend to become second-handers. The harder it is for us to get at the original meaning of the Bible, the more we will revert to the secondary literature" (83).
5. "Weakness in Greek and Hebrew also gives rise to exegetical imprecision and carelesseness. And exegetical imprecision is the mother of liberal theology."
6. "...when we fail to stress the use of Greek and Hebrew as valuable in the pastoral office, we create an eldership of professional academicians" (84). By this Piper means that it is no longer pastors who are the masters of the Word, but only those outside the church, those in seminaries and universities.
7. As a result of number 7, then, Piper contends there results a "depreciation of the pastoral office" (84).
8. Finally, in quoting Martin Luther, Piper warns that "if we neglect the literature [i.e. the Scriptures in the original languages] we shall eventually lose the gospel" (87).

What think you? Is Piper off course? Are the original languages that necessary?