First Sunday of Advent (NT)

1 Thessalonians 4:1-12
1 Finally, then, brothers, we ask and urge you in the Lord Jesus, that as you received from us how you ought to walk and to please God, just as you are doing, that you do so more and more. 2 For you know what instructions we gave you through the Lord Jesus. 3 For this is the will of God, your sanctification: that you abstain from sexual immorality; 4 that each one of you know how to control his own body in holiness and honor, 5 not in the passion of lust like the Gentiles who do not know God; 6 that no one transgress and wrong his brother in this matter, because the Lord is an avenger in all these things, as we told you beforehand and solemnly warned you. 7 For God has not called us for impurity, but in holiness. 8 Therefore whoever disregards this, disregards not man but God, who gives his Holy Spirit to you.
9 Now concerning brotherly love you have no need for anyone to write to you, for you yourselves have been taught by God to love one another, 10 for that indeed is what you are doing to all the brothers throughout Macedonia. But we urge you, brothers, to do this more and more, 11 and to aspire to live quietly, and to mind your own affairs, and to work with your hands, as we instructed you, 12 so that you may walk properly before outsiders and be dependent on no one.
The Holy Bible : English standard version. 2001 (1 Th 4:1-12). Wheaton: Standard Bible Society.

You know how you ought to live. you have been instructed in the way of the World. You have also been instructed in moral living. They knew how St Paul acted. Do you know how you are supposed to act? Abstain from sexual immorality. Do not transgress or sin in any way. Love your neighbor as yourself.

God has called you to be holy as He is Holy. Anything less and you have failed. you are no longer acting as a christian ought to act. But don't mourn your failing.

A basketball coach once told me, "Its not the last thing you did wrong, but the nest thing you do right." In various sports players will get distracted by their mistakes. But the player needs to focus on the next play. He can not undo the mistake. He can only do his best not to make the mistake again. This is your duty in Christian Love.

The Lord Jesus Christ has forgiven you all your sins. Your previous mistakes have been removed. Your slate wiped clean. He gives you his Love so you may share that with others. He gives you his Holy Spirit to help you to be Holy.