The Arthur Repp book on American catechisms brought up two affinities that help explain why Missouri and WELS headed so effortlessly into Calvinism.
One is the German language. As Repp explained, German-speaking church leaders in America had more affinity for each other than they had for the English-speaking leaders of parallel synods. A German Calvinist was a German first of all: easy to read, easy in conversation, sharing the same culture.
All the Lutheran groups in America were Pietists, so that was not a key difference. They all blended plenty of Pietism with their newly discovered Confessional roots. They all added more or less of Lutheran doctrine to their Pietism, an amalgamation that could not last.
The second affinity was rationalism. Just as the Pietist Delitsch veered into rationalism (advocating two Isaiahs), so the Synodical Conference leaders were drawn into rationalism, which was natural to Pietism and Calvinism.
The cornerstone of UOJ thinking is a rationalistic pratfall. Thus - If Jesus became sin on behalf of mankind, then mankind became righteous at the same moment: Universal Objective Justification.
For UOJ Enthusiasts, the atonement and justification are the same thing, because of that argument. However, the argument is fallacious, because justification is not the same as the atonement.
The Gospel message is the atonement - Christ crucified for the sins of the world. That is the treasure, as the Book of Concord says, in harmony with Luther.
The Holy Spirit distributes that treasure through the Means of Grace. The invisible Word of preaching and teaching plants faith in individuals. The visible Word of Holy Baptism does the same in infants. The visible Word of Holy Communion sustains faith. All the Means of Grace accomplish what God promises - the declaration of forgiveness. Grace comes to the sinner only through Means, never without the Word.
The same rationalism is at work in the assumption that mankind was justified when Jesus rose from the dead. Because 1 Timothy 3:16 says Jesus was justified in the Spirit, that phrase is used to claim the world was also justified. Who advanced that line of thinking? - the Halle Pietist Rambach, echoed by Jay Webber, the Buchholz peritus.
There is no intention to make a perfect parallel between Jesus and mankind in 1 Timothy 3:16. Jesus was not a sinner in need of forgiveness. His resurrection showed that He was perfect in holiness. To equate Jesus with mankind is to make Him in need of forgiveness and sharing that forgiveness instantly with all of mankind, Hottentots and Hindus alike, even before birth.
Although it is fair to show the inherent conflicts within UOJ, such as the Keys, infant baptism, or excommunication of the pre-forgiven, the biggest errors are the foundational ones - Enthusiasm and rationalism. Everything else is a symptom.
The SynConference will not teach justification by faith correctly until
- its leaders repent,
- repudiate the Stephan-Walther UOJ,
- and teach in conformity with the Scriptures and Confession.