Matthew 18:15-17
New International Version (NIV)
Dealing With Sin in the Church
15 “If your brother or sister[a] sins,[b] go and point out their fault, just between the two of you. If they listen to you, you have won them over. 16 But if they will not listen, take one or two others along, so that ‘every matter may be established by the testimony of two or three witnesses.’[c] 17 If they still refuse to listen, tell it to the church; and if they refuse to listen even to the church, treat them as you would a pagan or a tax collector.
Sometimes catechism might take primacy over evangelization.
Again which comes first? The Gospel or instructions in obedience? Do the 10 commandments save us?
The Matthew 18 reference in context teaches us how we are to handle sin within the church. Which neither one of us could cast stones on the other given we both know every church out there is not in full obedience of this passage.