Ignatius of Antioch

Pray without ceasing on behalf of other people. There is always hope for the repentance that they may attain before God. For "cannot he who falls arise again, and he who goes astray return?" Permit them, then, to be instructed by you. Be therefore the ministers of God and the mouth of Christ. For thus says the Lord, "If you take forth the precious from the vile, you shall be as my mouth." Be humble in your earnest prayers. While they go astray, stand steadfast in the faith.

As children of light and truth, flee from division and wicked doctrines. Where the shepherd is, there you follow as sheep. For there are many wolves that appear trustworthy, who, by means of a pernicious pleasure, carry captive those that are running toward God, but they shall have no place in your unity. So, as children of light and truth, avoid the dividing your unity and the wicked doctrine of the heretics, from whom “a defiling influence has gone forth into all the earth.”