Why Don’t They Go Together?
You are studying these topics correctly, for they are like large tectonic doctrines that come together in a gridlock.
Indeed, there is an impasse with universal justifying grace (1 John 2:2), original sin (Ephesians 2:1), and God’s election of individuals (Romans 8:29-30). Because of this gridlock, temptation arises to harmonize and alleviate the tension through the placement and/or role of faith in conversion. It must be stated though that Martin Luther understood this impasse, but never tried to harmonize the teachings. He feared that he would be forced to make concessions that would violate Biblical truth, if harmonization took place.
What this means is that the doctrines are to remain in gridlock and tension. Resist trying to harmonize them, for once you attempt to harmonize them you either go the way of Calvinism or the way of Arminianism. In other words, trying to harmonize or alleviate the gridlock with these doctrines will initiate a domino effect, consequently changing the role of the pastor office, the role of the sacraments, and the nature of the church.
Best suggestion? Leave them in gridlock; leave them in tension. The tension actually leads to the proclamation of Christ.
If you would like to learn more on this subject, you may enjoy the following paper:
Why the Doctrine of Predestination Matters
Grace and peace,
Zion Lutheran Church