Augustine of Hippo, on 1John 4:21

“And this commandment we have from God, that he, who loveth God, love also his brother.”

“"For he that loveth not his brother whom he seeth, how can he love God whom he seeth not? And this commandment have we from Him, that he who loveth God love his brother also." Marvellous fine talk it was, that thou didst say, "I love God," and hatest thy brother! O murderer, how lovest thou God? Hast thou not heard above in this very epistle, "He that hateth his brother is a murderer"? Yea, but I do verily love God, however I hate my brother. Thou dost verily not love God, if thou hate thy brother.”

Imported from an open dataset — not yet checked against the printed edition.