Easton's Bible Dictionary (1897)
Good is Jehovah, my Lord, a Levite sent out by Jehoshaphat to instruct the people of Judah in the law (2 Chr. 17:8).
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
TOB-ADONI'JAH (good is my Lord Jehovah), one of the Levites sent by Jehoshaphat to teach Judah the law of the Lord. 2 Chr 17:8.
Hitchcock's Bible Names (1869)
my good God; the goodness of the foundation of the Lord