Compared to the JB, the NJB translation is in general more literal, but in some places less accurate due to gender inclusiveness. There is also now a RNJB (2019).
The main difference is that the New Jerome Biblical Commentary (1990) is a revised edition of the original JBC (1968). Same editors, but articles/entries have been updated. I haven’t closely compared the two side-by-side (I don’t own the original 1968 edition). But I do own the NJBC.
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