Blessed be the God and Father of our Lord Jesus Christ, who has blessed us in Christ with every spiritual blessing in the heavenly places, even as he chose us in him before the foundation of the world, that we should be holy and blameless before him in love. He predestined us for adoption as sons through Jesus Christ, according to the purpose of his will, to the praise of his glorious grace, with which he has blessed us in the Beloved. In him we have redemption through his blood, the forgiveness of our trespasses, according to the riches of his grace, which he lavished upon us, in all wisdom and insight making known to us the mystery of his will, according to his purpose, which he set forth in Christ as a plan for the fullness of time, to unite all things in him, things in heaven and things on earth.

even as he chose us in him before the foundation of the world, that we should be holy and blameless before him in love.

This is all one run-on sentence. Many translations put a period after “before him,” and then begin the next sentence, “In love he predestined…”

I think the period belongs where I have put it above so that it reads that God chose us that we should be “holy and blameless before him in love.”

My reasoning is this: Paul will later exhort the Ephesians to do what they were chosen to do:

3.17: “that you, being rooted and grounded in love,…”

4.2: “with all humility and gentleness, with patience, bearing with one another in love”

4.15: ”Rather, speaking the truth in love, we are to grow up in every way into him who is the head, into Christ,”

4.16: “makes the body grow so that it builds itself up in love.”

5.1-2: “Therefore be imitators of God, as beloved children and walk in love”

In all these ways Paul instructs his readers how they can behave in a holy and blameless manner in love. God has chosen them for this and given them access to himself (i.e. holiness, “saints”) so that they must act in an appropriate manner to their new position (“holy”).