In the salutation…
Paul, an apostle of Christ Jesus by the will of God, to the saints who are at Ephesus and who are faithful in Christ Jesus: Grace to you and peace from God our Father and the Lord Jesus Christ. (Ephesians 1:1-2)
Paul opens his letter to the Ephesians with a warm greeting offered twice-over. In this salutation, Paul presents the dual source of his apostolic authority, a dual designation of believers, offers a dual blessing to those believers, and points them to the dual source of their blessing.