I have now completed what Gentry (and Wellum) have to say about the Mosaic and Davidic covenants and am beginning the section on the new covenant.
A lot of it is very helpful. It is clearly written . Large chunks of it are rather detailed exegesis which I confess I read lightly as I am interested in finding out the main thrust of the argument. However one can't skip too much or the argument can be missed.
Also, why do scholars feel the need in such books to enter into lengthy debates with other scholars and copy out long citations from them which they then proceed to demolish? I suppose other academics may be interested, but it is not exactly what the busy pastor needs. As with many such books, one skips the detail - I cannot remember it anyway, but at least I know it is there if I need to go back to it.
On the Mosaic covenant, the predictable point is made that the Ten Commandments are part of one indivisible law that is all part of the old covenant, and any attempt to distinguish between civil, moral and ceremonial law is an 'imposition' from outside the text. I don't think any Reformed commentator would disagree that the law is given as a package, but (i) nothing is said of the many good arguments for seeing distinctions, as for example suggested by Philip Ross in 'From the Finger of God'; (ii) nothing is said about the very obviously different way in which the Ten Commandments (or 'Words) are given over against the rest of the law. Surely this is within the domain of biblical theology - one does not have to delve into the mysterious waters of systematics to discuss that.
I look forward to more on the new/everlasting covenant - at present I am looking at what they say about Isaiah 54,55 and Ezekiel before the chapter dealing with Jeremiah.