Note 12 at Eph. 2:17: Verse 17 seems to be an allusion to Isaiah 57:19 (see O.T. scripture cited in v. 17). Through Jesus mankind can now be reconciled (see note 11 at 2 Cor. 5:18, p. 1006) to God and to each other.

It is "through him" (Jesus Christ; v. 18) and His death that Jew and Gentile may now come boldly unto his throne of grace (Heb. 4:16). The Gentiles who were far off, having no hope and without God in this world (v. 12), and Jews who were near because of the covenants of promise are now IN Christ Jesus (v. 13). How much better it is to be IN Christ Jesus than to be just near.

Prior to this, the Jew could approach God through his mediator the high priest, and the Gentile could approach God by his conversion to Judaism. But now, Jesus has become the door whereby everyone may come to God on the basis of faith in what Jesus has done for him alone.