Charles Ellicott Commentary 2 Chronicles 23:11

"Then they brought out the king`s son, and put the crown upon him, and [gave him] the testimony, and made him king: and Jehoiada and his sons anointed him; and they said, [Long] live the king." — 2 Chronicles 23:11 (ASV)

Then. — And. So in 2 Chronicles 23:14; 2 Chronicles 23:17.

They brought out ... and put. — 2 Kings 11:12: he (Jehoiada) brought out ... and put.

Put upon him the crown, and gave him the testimony. —Literally, put upon him the crown (nçzer; Exodus 29:6; 2 Samuel 1:10) and the law (ha-’êdûth; Exodus 25:21–22; Exodus 31:18).

Was a scroll of the ten words wrapped round the diadem, or laid on the king’s shoulder? (Compare to Vulgate, “imposuerunt ei diadema testimonium dederuntque in manu ejus tenendam legem; ” as if a copy of the law was solemnly presented to the newly-crowned king.)

Jehoiada and his sons. —The chronicler adds this to make it clear that it was the priests who anointed the king. (Compare to 1 Kings 1:39.)