"At the end of the day my brothers, the issue that is at stake in divine election and in effectual redemption is not a matter of whether you argue about the five points of Calvinism. At the end of the day it's a matter of the harmony of the Trinity.
Have the Father and the Son and the Holy Spirit a harmony in their purposes? Does God plan something, that the Son effects, that the Spirit fails to bring to fruition?
No Paul says, God's plan for the fullness of time is going to be effected because this is the God who works out all things (verse 11) according to the counsel of His will... in order that at the end of the day His predestining purpose that we should be adopted through Jesus Christ according to the purpose of His will (verse 5) might see us conformed to the likeness of His Son. And that's the thing that God has set His heart upon... conforming His elect to the likeness of His Son.
And mark Paul's words, He will let nothing stand in the way of fulfilling that purpose... and honoring His Son and honoring His Son's death. He will certainly not let my puny will stand in the way of His Son's eternal glory."