Some of the sentence structure here is really too complex for encyclopedic writing. In the case of 

 :His books explore Jewish understandings of the Law (or Torah) in the "age to come" or messianic era, examine Paul and his theology in light of his Sermon on the Mount in Matthew against the backdrop of developments and thought in Judaism not only during the time of Jesus but also in the closing decades of the first century (especially the destruction of Jerusalem and the Council of Jamnia). 

 I'm not understanding what is being said (should the second "his" be "the"?), and the sentence probably should be split into two or more.