Galatians 3:19a – Why then the law? It was added because of transgressions,
If the Bible is about God fulfilling His promise to Abraham then why did God give the Law at all? Why all these rules that form part of the law? The law was added because of sin. People are sinners and unless they are made aware of it they are going to perish in their sins and never come to realize the benefits of the covenant between Abraham and God.
The Law lets us know that we are sinners, we come to see, through the preaching of the Gospel, that we need Jesus Christ. This is a strong argument for the fact that in the presentation of the Gospel we must, in some fashion, but with plainness and clarity, tell people that they are lawbreakers.
Where there is no sin there is no need for a Saviour. The life and death and resurrection make no sense at all if there is not a Law that He keeps, which we have broken, which demands punishment and which God is determined to punish and yet just as determined not to punish us even though we deserve it. Give people the Good News regarding Jesus Christ. But be sure that the news is not good and will make no sense if we do not relay to them that they are Lawbreakers of a Holy God’s Law and that such behaviour deserves and will receive the wrath of God if sinners are not hidden in Christ.
Only Christ is righteous. Unless His righteousness is counted as ours we will have to stand before Gos with our own. That just isn’t sufficient.