Adam Clarke on Psalms 2:10

Be wise - O ye kings - An exhortation of the Gospel to the rulers of all kingdoms, nations, and states, to whom it may be sent. All these should listen to its maxims, be governed by its precepts, and rule their subjects according to its dictates.

Be instructed, ye judges - Rather, Be ye reformed - cast away all your idolatrous maxims; and receive the Gospel as the law, or the basis of the law, of the land.