Giovanni Diodati (1576-1649) was a Swiss-Italian Reformed theologian and the first person to translate the Bible into Italian from the Hebrew and Greek. He is also known for his commentary on the Bible, translated into English under the title Pious and Learned Annotations upon the Holy Bible. Below is his commentary on Ephesians 1:4-6. I have slightly modified the structure for greater clarity:
Ephesians 1:4-6. 4 According as he hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love: 5 Having predestinated us unto the adoption of children by Jesus Christ to himself, according to the good pleasure of his will, 6 To the praise of the glory of his grace, wherein he hath made us accepted in the beloved.
According as] viz. According as God by his election from everlasting framed a new body of human race (opposite to the first whereof Adam was head, in whom all men have sinned and are dead) and appointed Christ to be its head, that in him it might be all gathered together, and by him made partaker of his grace, life, and glory: so he bringeth this his decree to pass in his appointed time; bestowing all his favours upon his Church by Christ in this sacred communion: see Ephes. 3. 11. 2 Tim. 1. 9.
In him] he showeth hereby, that this election is free, and undeserved, and not in regard of any good foreseen in us.
That we should] viz. that in the kingdom of heaven, after our sanctification hath been brought to perfection, we may enjoy the sight of his face, and steadfast conjunction with him in perfect charity: see Ephes. 5. 27. Col. 1. 22. Or that we should be holy] he doth not say, because we were holy, or that he did foresee we would be so; for our holiness is so far from being the cause of our election, that rather it is an effect of it, because God hath called them whom before he had elected, and afterwards justified, &c. Rom. 8. 30.
Adoption of children] viz. To become his children. In this verse two causes, why we are elected or predestinated to salvation; the first is Gods good pleasure, as the efficient cause; the other is Jesus Christ, as the material cause; and in the verse following, he shows the final cause; namely, the honour and glory of God.
To himself] Fr. For himself; viz. to make us his, and eternally unite us to himself; Or, for his glories end: as Rom. 11. 36.
Of the Glory] Namely, of his glorious and admirable favour, by which he hath powerfully brought to an end the work of mans salvation: see Rom. 9. 23. 2 Cor. 4. 4.
In the beloved] namely, for the love, and in regard of Christ only who hath all the Fathers love, not only as he is everlasting Son, but also as he is perfectly obedient, and just in his human nature, and quality of Mediator, Mat. 3. 17. John 1. 16. & 3. 35. & 10. 7. Rom. 15. 15.