Charles Ellicott Commentary 1 Chronicles 12:27

"And Jehoiada was the leader of [the house of] Aaron; and with him were three thousand and seven hundred," — 1 Chronicles 12:27 (ASV)

And Jehoiada ... — Literally, And Jehoiada the prince (hannagîd, 1 Chronicles 9:11; 1 Chronicles 9:20) belonging to Aaron. Aaron is used as the name of the leading clan of Levi.

Jehoiada is perhaps father of the Benaiah of 1 Chronicles 11:22. He was not high priest (Abiathar, 1 Samuel 23:9), but head of the warriors of his clan.

It is not clear whether the 3,700 are included in the 4,600 of 1 Chronicles 12:26 or not. Probably not.

Was ... were. —Omit.