Adam Clarke on 2 Kings 14:14

And he took - hostages - התערבות hattaaruboth, pledges; from ערב arab, to pledge, give security, etc., for the performance of some promise. See the meaning of this word interpreted in the note on Gen 38:17 (note). It is likely that Amaziah gave some of the nobles or some of his own family as hostages, that he might regain his liberty; and they were to get their liberty when he had fulfilled his engagements; but of what kind these were we cannot tell, nor, indeed, how he got his liberty.