Jamieson, Fausset & Brown

Jerusalem--In Jer 23:6, instead of this, it is "Israel." "The name" in the Hebrew has here to be supplied from that passage; and for "he" (Messiah, the antitypical "Israel"), the antecedent there (Isa 49:3), we have "she" here, that is, Jerusalem. She is called by the same name as Messiah, "The Lord Our Righteousness," by virtue of the mystical oneness between her (as the literal representative of the spiritual Church) and her Lord and Husband. Thus, whatever belongs to the Head belongs also to the members (Eph 5:30, Eph 5:32). Hence, the Church is called "Christ" (Rom 16:7; Co1 12:12). The Church hereby professes to draw all her righteousness from Christ (Isa 45:24-25). It is for the sake of Jerusalem, literal and spiritual, that God the Father gives this name (Jehovah, Tsidkenu, "The Lord our Righteousness") to Christ.