Eph 1:1
To the saints who are in Ephesus, and faithful in Christ Jesus:
To the saints who are at Ephesus, that is, to the Christians who were members of the church at Ephesus, the metropolis of Asia. He calls them saints, for such they were in profession, such they were bound to be in truth and reality, and many of them were such. All Christians must be saints; and, if they come not under that character on earth, they will never be saints in glory.
He calls them the faithful in Christ Jesus, believers in him, and firm and constant in their adherence to him and to his truths and ways. These peculiar blessings proceed from God, not as a Creator, but as a Father by special relation: and they come from our Lord Jesus Christ, who, having purchased them for his people, has a right to bestow them upon them. Indeed the saints, and the faithful in Christ Jesus, had already received grace and peace; but the increase of these is very desirable, and the best saints stand in need of fresh supplies of the graces of the Spirit, and cannot but desire to improve and grow: and therefore they should pray, each one for himself and all for one another, that such blessings may still abound unto them.
Every Christian is a saint, because every Christian has been set apart and made holy through the perfect righteousness of Christ that has been placed to his account (Rom. 3:21–22; 1 Cor. 1:30; Phil. 3:9; etc.). When a person acts in faith to receive Christ, God acts in grace to give that person Christ’s own righteousness. It is Christ’s perfect righteousness—not a person’s own character or accomplishments, no matter how great they may seem in men’s eyes—that establishes every believer as one of God’s saints through saving faith.
The word “Saint” is interesting to me. I have not really ever thought of myself as a “Saint” per-say but I am positionally that. My actions should reflect someone who has such high standards placed upon him. I am a saint – and I should act like one, for if I do not –then I am not. Actions of a saint are founded in the next phrase – Faithful in Christ Jesus. Faithfulness is what the Father wants from me – to walk in such a way that reflects my commitment to Him as Lord.
Information taken from Matthew Henry’s – and John MacArthur’s Commentaries