The link above is a helpful, and brief, opinion piece by John Piper concerning whether current pastors and would be pastors should pursue PhD study. For current pastors he says:
If you’re already a pastor, I wouldn’t get a PhD. It’s a lot of work, and the payoff is really small. Really small.
When I say really small, I don’t mean studying the Bible is small payoff. But the way most PhD programs are set up it is small payoff. Because you have to read so much junk in order to get your PhD. You have to become an expert in what other people are saying, most of which is wrong.
Later, he says:
And if you’re a pastor, set yourself to study the Bible and take courses. But don’t worry about a degree for goodness’ sake.
I love this. The thing about PhD study, as John Piper says, is that you spend years becoming an expert in a few verses. One can get a degree and be surprisingly ignorant about the Bible outside of the area studied. Instead, pastors should seek to be experts in the whole Bible, or at least seek to grow in their understanding of the whole Bible. I don’t know of a program where you can pursue that (Piper says there are some, but I don’t know what they are).