Eph. 1: 4 just as He chose us in Him before the foundation of the world, that we would be holy and blameless before Him. In love 5 He predestined us to adoption as sons through Jesus Christ to Himself, according to the kind intention of His will, 

St. Augustine on Ephesians 1:3
Chapter 34
Therefore He chose them out of the world while He was wearing flesh, but as those who were already chosen in Himself before the foundation of the world. This is the changeless truth concerning predestination and grace. For what is it that the apostle says, As He has chosen us in Himself before the foundation of the world? Ephesians 1:4 And assuredly, if this were said because God foreknew that they would believe, not because He Himself would make them believers, the Son is speaking against such a foreknowledge as that when He says, You have not chosen me, but I have chosen you; when God should rather have foreknown this very thing, that they themselves would have chosen Him, so that they might deserve to be chosen by Him. Therefore they were elected before the foundation of the world with that predestination in which God foreknew what He Himself would do; but they were elected out of the world with that calling whereby God fulfilled that which He predestinated.

Chapter 36.— God Chose the Righteous; Not Those Whom He Foresaw as Being of Themselves, But Those Whom He Predestinated for the Purpose of Making So.Therefore, says the Pelagian, He foreknew who would be holy and immaculate by the choice of free will, and on that account elected them before the foundation of the world in that same foreknowledge of His in which He foreknew that they would be such. Therefore He elected them, says he, before they existed, predestinating them to be children whom He foreknew to be holy and immaculate. Certainly He did not make them so; nor did He foresee that He would make them so, but that they would be so. Let us, then, look into the words of the apostle and see whether He chose us before the foundation of the world because we were going to be holy and immaculate, or in order that we might be so. Blessed, says he, be the God and Father of our Lord Jesus Christ, who has blessed us in all spiritual blessing in the heavens in Christ; even as He has chosen us in Himself before the foundation of the world, that we should be holy and unspotted.Ephesians 1:3 Not, then, because we were to be so, but that we might be so. Assuredly it is certain — assuredly it is manifest. Certainly we were to be such for the reason that He has chosen us, predestinating us to be such by His grace. Therefore He blessed us with spiritual blessing in the heavens in Christ Jesus, even as He chose us in Him before the foundation of the world, that we should be holy and immaculate in His sight, in order that we might not in so great a benefit of graceglory concerning the good pleasure of our will.

Chapter 38
He therefore chose and predestinated us in Christ before the foundation of the world. Although the apostle says that it was not because He foreknew that we should be such, but in order that we might be such by the same election of His grace, by which He showed us favour in His beloved Son. When, therefore, He predestinated us, He foreknew His own work by which He makes us holy and immaculate. Whence the Pelagian error is rightly refuted by this testimony. But we say, say they, that God did not foreknow anything as ours except that faith by which we begin to believe, and that He chose and predestinated us before the foundation of the world, in order that we might be holy and immaculate by His grace and by His work. But let them also hear in this testimony the words where he says, We have obtained a lot, being predestinated according to His purpose who works all things.Ephesians 1:11

Taken from the link below.
http://www.newadvent.org/fathers/15121.htm

Calvin on Ephesians 1:4

Verse 44.According as he hath chosen us. The foundation and first cause, both of our calling and of all the benefits which we receive from God, is here declared to be his eternal election. If the reason is asked, why God has called us to enjoy the gospel, why he daily bestows upon us so many blessings, why he opens to us the gate of heaven, — the answer will be constantly found in this principle, that he hath chosen us before the foundation of the world. The very time when the election took place proves it to be free; for what could we have deserved, or what merit did we possess, before the world was made? How childish is the attempt to meet this argument by the following sophism! “We were chosen because we were worthy, and because God foresaw that we would be worthy.” We were all lost in Adam; and therefore, had not God, through his own election, rescued us from perishing, there was nothing to be foreseen. The same argument is used in the Epistle to the Romans, where, speaking of Jacob and Esau, he says,“For the children being not yet born, neither having done any good or evil, that the purpose of God according to election might stand, not of works, but of him that calleth.” (Romans 9:11.)But though they had not yet acted, might a sophist of the Sorbonne reply, God foresaw that they would act. This objection has no force when applied to the depraved natures of men, in whom nothing can be seen but materials for destruction.In Christ. This is the second proof that the election is free; for if we are chosen in Christ, it is not of ourselves. It is not from a perception of anything that we deserve, but because our heavenly Father has introduced us, through the privilege of adoption, into the body of Christ. In short, the name of Christ excludes all merit, and everything which men have of their own; for when he says that we arechosen in Christ, it follows that in ourselves we are unworthy

Verse 5
Verse 55.Who hath predestinated us. What follows is intended still further to heighten the commendation of divine grace. The reason why Paul inculcated so earnestly on the Ephesians the doctrines of free adoption through Christ, and of the eternal election which preceded it, has been already considered. But as the mercy of God is nowhere acknowledged in more elevated language, this passage will deserve our careful attention. Three causes of our salvation are here mentioned, and a fourth is shortly afterwards added. The efficient cause is the good pleasure of the will of God, the material cause is, Jesus Christ, and the final cause is,the praise of the glory of his grace. Let us now see what he says respecting each.To the first belongs the whole of the following statement God hath predestinated us in himself, according to the good pleasure of his will, unto the adoption of sons, and hath made us accepted by his grace. In the word predestinate we must again attend to the order. We were not then in existence, and therefore there was no merit of ours. The cause of our salvation did not proceed from us, but from God alone. Yet Paul, not satisfied with these statements, adds in himself. The Greek phrase is , εἰς αὑτὸν, and has the same meaning with ἐν αὑτῷ. By this he means that God did not seek a cause out of himself, but predestinated us, because such was his will.But this is made still more clear by what follows, according to the good pleasure of his will. The word will was enough, for Paul very frequently contrasts it with all outward causes by which men are apt to imagine that the mind of God is influenced. But that no doubt may remain, he employs the word good pleasure, which expressly sets aside all merit. In adopting us, therefore, God does not inquire what we are, and is not reconciled to us by any personal worth. His single motive is the eternal good pleasure, by which he predestinated us. (109) Why, then, are the sophists not ashamed to mingle with them other considerations, when Paul so strongly forbids us to look at anything else than the good pleasure of God?Lest anything should still be wanting, he adds , ἐχαρίτωσεν ἐν χάριτι (110) This intimates, that, in the freest manner, and on no mercenary grounds, does God bestow upon us his love and favor, just as, when we were not yet born, and when he was prompted by nothing but his own will, he fixed upon us his choice. (111)The material cause both of eternal election, and of the love which is now revealed, is Christ, the Beloved. This name is given, to remind us that by him the love of God is communicated to us. Thus he is the well-beloved, in order that we may be reconciled by him. The highest and last end is immediately added, the glorious praise of such abundant grace. Every man, therefore, who hides this glory, is endeavoring to overturn the everlasting purpose of God. Such is the doctrine of the sophists, which entirely overturns the doctrine of Christ, lest the whole glory of our salvation should be ascribed undividedly to God alone.

Taken from the link below.
https://www.studylight.org/commentaries/cal/ephesians-1.html

HT: The Protestant Reformation