“The implication of Ephesians 1:4–6 is that the grace of God is the apex of His glory. His goal is not just ‘the praise of His glory.’ It is ‘the praise of the glory of His grace.’
That is, the constellation of excellencies that make up the glory of God reach their most beautiful overflow in the expression of grace for undeserving sinners like us. And what has now become clear in the enactment of the new covenant ‘in His blood’ is that the humble, willing, obedient suffering of Christ for sinners is the apex of God’s grace—the place where that grace is most beautifully on display.
So grace is the consummate expression of God’s glory, and Christ in His suffering is the consummate expression of grace. Three times in Ephesians 1:4–6 Paul clarifies that the aim of praising ‘the glory of God’s grace’ is achieved ‘through Jesus Christ’:
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 to Himself 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.’ ‘Through Jesus Christ.’ ‘In the Beloved.’ We know that these phrases are references to Christ’s work on the cross because in the next verse Paul says, ‘In Him we have redemption through His blood, the forgiveness of our trespasses, according to the riches of His grace’ (Ephesians 1:7).
Therefore, the ultimate goal of God in His saving providence— namely, the praise of the glory of His grace— was achieved through the suffering of the Son of God, who died to deliver us from eternal suffering (2 Thess. 1:9) and bring us into everlasting enjoyment of His glory (John 17:24).”
–John Piper, Providence (Wheaton, IL: Crossway, 2020), 170–171.