The other main problem with your position is that it interprets the WELS statement as having a meaning which it does not have. Everyone who had anything to do with the WELS statement believes the church's assignment is to preach the gospel. No one thinks we have power to make believers by our own power. But those who preach or teach or baptize are the instruments which the Holy Spirit uses to deliver the gospel. The gospel is the instrument that he uses to create faith.
Faith is the instrumental cause of forgiveness.
We are justified by faith. If your criticism of the WELS statement is valid, it is equally valid against Paul. Paul regarded himself as an instrument through whom people became believers. No matter how you interpret it, the WELS statement does not say anything different than what Paul says. WELS.net content is copyrighted unless otherwise stated.