Let us not merely call him Lord, for that will not save us. For he says, “Not everyone who says to me, Lord, Lord, will be saved, but he who does what is right” (Matt. 7:21). Thus, brothers, let us acknowledge him by our actions, by loving one another, by refraining from adultery, backbiting, and jealousy, and by being self-controlled, compassionate, kind. We ought to have sympathy for one another and not to be avaricious. Let us acknowledge him by acting in this way and not by doing the opposite. We ought not to have greater fear of men than of God. That is why, if you act in this way, the Lord said, “If you are gathered with me in my bosom and do not keep my commands, I will cast you out and will say to you: ‘Depart from me. I do not know whence you come, you workers of iniquity.’”
--St. Clement of Alexandria
For you must keep in mind that the shedding of Our Lord's blood and the sacrifice of His life were just as necessary to wipe out venial sin as to deliver you from mortal sin. Remember that anyone who attaches little importance to venial sin will soon fall into mortal sin. If you do not find these resolutions in you own soul, pray to Our Lord to put them there, and do not rest until you possess these dispositions. For you ought to know that as long as you do not have the will to die or suffer every kind of disgrace and torture rather than commit any sin, you are not a true Christian.
There is only one thing more dangerous than sin--the murder of a man’s sense of sin. 
