Proverbs 21:27

27The sacrifice of the wicked is an abomination;
How much more when he brings it with wicked intent!
-Proverbs 21:27

Have you ever wondered why our good works were called filthy rags? There is a concept well understood by the Jewish reader that we often miss. First off, our good works in Christ Jesus are no longer filthy rags. But those that were offered in the flesh are displeasing to the Lord. When something dirty comes in contact with a rag, that rag becomes dirty. If that rag were to touch something clean, it would not become dirty. That which was offered in the flesh was in contact with wickedness. No sacrifice offered in that case would be pleasing to the Lord. Therefore, the sacrifice of Jesus, who was perfect, could truly be pleasing in the sight of the Lord. What we offer before the Lord must be offered in Spirit and in Truth. It must be offered through Jesus who is the only One that purifies.