
Wrong teaching must be addressed. Serious errors (heresies like denying the fundamental doctrines of the faith, or corrupting the gospel) can't be tolerated ever.
Real Christians hold a broad range of errors (Calvinism, Arminianism, Charismaticism, errors on baptism, etc.) on matters that are definitely not unimportant, and we further divide the body if we refuse to fellowship with folks who hold such errors, simply because they hold them.
We have to give account to the Lord for addressing error, but we also have to give account for whether or not we loved the Lord's blood-bought believers despite their errors.
For me as someone who is exceptionally truth focused, this can be a painful exercise.

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