Jamieson, Fausset and Brown on Nehemiah 8:7-8

7-8. caused the people to understand the law ... gave the sense--Commentators are divided in opinion as to the import of this statement. Some think that Ezra read the law in pure Hebrew, while the Levites, who assisted him, translated it sentence by sentence into Chaldee, the vernacular dialect which the exiles spoke in Babylon. Others maintain that the duty of these Levites consisted in explaining to the people, many of whom had become very ignorant, what Ezra had read.