Galatians 2:4, 5, 12-16, 21
This issue arose because some false brothers were brought in under false pretenses to spy on our freedom in Christ Jesus, in order to enslave us. . . .

Galatians 4:9-12
But now that you know God, or rather are known by God, how is it that you are turning back to those weak and worthless principles? Do you wish to be enslaved by them all over again? . . .

Galatians 5:11
Now, brothers, if I am still preaching circumcision, why am I still being persecuted? In that case the offense of the cross has been abolished.

Romans 14:15
If your brother is distressed by what you eat, you are no longer acting in love. Do not by your eating destroy your brother, for whom Christ died.

1 Corinthians 8:11, 12
So this weak brother, for whom Christ died, is destroyed by your knowledge. . . .