"Moreover the law entered, that the offence might abound. But where sin abounded, grace did much more abound:" (Romans 5: 20)
The law was never God's main agenda.
The law is a standard which no man can keep, and a standard which every man needs to see so that he will stop trying to keep it.
"Now we know that what things soever the law saith, it saith to them who are under the law: that every mouth may be stopped, and all the world may become guilty before God." (Romans 3: 19)
In Galatians, Paul explained that the law was for the Jews, to prepare them for the coming Messiah:
"23But before faith came, we were kept under the law, shut up unto the faith which should afterwards be revealed. 24Wherefore the law was our schoolmaster to bring us unto Christ, that we might be justified by faith. 25But after that faith is come, we are no longer under a schoolmaster." (Galatians 3: 23-25)
Now, we find that when Adam sinned, all men died with him:
"But not as the offence, so also is the free gift. For if through the offence of one many be dead, much more the grace of God, and the gift by grace, which is by one man, Jesus Christ, hath abounded unto many." (Romans 5: 15)
With the ongoing, never ending gift of righteousness and abundance of grace, we reign in life, His Life:
"For if by one man's offence death reigned by one; much more they which receive abundance of grace and of the gift of righteousness shall reign in life by one, Jesus Christ." (Roman 5:17)
The bad which man did, God made work for good. Even when we sin (verb) God's grace superabounds in our lives.
Notice that we are not invited then to sin willfully:
"1What shall we say then? Shall we continue in sin, that grace may abound? 2God forbid. How shall we, that are dead to sin, live any longer therein? 3Know ye not, that so many of us as were baptized into Jesus Christ were baptized into his death? " (Romans 6: 1-3)
All throughout the Old Testament, God's grace superabounded in the midst of man's greatest failures. The geneaology of Jesus, found in the Gospel of Matthew, focuses on four women - Tamar, Rahab, Ruth, and Bathsheba -- all women who would have been disqualified because of their Gentile status )Ruth), their sin (Bathsheba, Tamar), or both (Rahab) if not for the grace of God.
When we realize how forgiven we are, we receive His life, and no longer find ourselves under sin, but rather under grace:
"12Let not sin therefore reign in your mortal body, that ye should obey it in the lusts thereof. 13Neither yield ye your members as instruments of unrighteousness unto sin: but yield yourselves unto God, as those that are alive from the dead, and your members as instruments of righteousness unto God. 14For sin shall not have dominion over you: for ye are not under the law, but under grace. 15What then? shall we sin, because we are not under the law, but under grace? God forbid." (Romans 6: 12-15)
"11For the grace of God that bringeth salvation hath appeared to all men, 12Teaching us that, denying ungodliness and worldly lusts, we should live soberly, righteously, and godly, in this present world; 13Looking for that blessed hope, and the glorious appearing of the great God and our Saviour Jesus Christ; 14Who gave himself for us, that he might redeem us from all iniquity, and purify unto himself a peculiar people, zealous of good works." (Titus 2:11-14)
Even when we fail, let us never think that God's grace will fail for us, for even when sin increased, God's grace superabounds and overflows.