Jesus said it best:
Mat 15:11 Not that which goeth into the mouth defileth a man; but that which cometh out of the mouth, this defileth a man.
The Jews had one way to God- His way. This was a type and shadow of what we have in Christ. To violate one section of the law was to be guilty of all the law, to step outside of God's prescribed path was to step outside of God's path to salvation. Sacrifice, sanctifcation , cleansing, purity from defilement- all these admonitions of the law were pictures of our inheritance in Christ.
Joh 14:6 Jesus saith unto him, I am the way, the truth, and the life: no man cometh unto the Father, but by me.
Jesus is our way.
Jesus Christ fulfilled the law, no one had or could before or after Him. We receive His righteousness by faith and on that basis we are acceptable to God. Your deeds could not have earned salvation before or after Christ.
Rom 6:14 For sin shall not have dominion over you: for ye are not under the law, but under grace.