Now we know that whatever the law says it speaks to those who are under the law, so that every mouth may be stopped, and the whole world may be held accountable to God. (ESV)
Truth has a way of silencing the arguments of fools. Have you ever known someone who seemed to be able to talk themselves out of any kind trouble? There are people who are very clever in defending themselves. There is a judgment coming that will show people for the guilty rebels that they are. No clever words will be able to get them out of their trouble.
Every man and women will stand before God and give an account for the reality of their breaking God's Law. When Paul says that "every mouth may be stopped," he is saying that there will be no argument a man can raise that will get him out of his trouble. You may have fooled people on this earth. You may have even fooled yourself. You will not fool God.
There are two aspects of the law that are spoken of here; those who received God's Law, and those who have God's law written on their hearts. Jews and Gentiles alike are guilty. The entire world stands before God completely guilty. No Jew can say that they have an excuse. They had the Law of Moses given to them. No Gentile has an excuse. Nature itself gives man God's Law.
It is important for us to realize just how guilty we are. God's standard is absolute perfection. The Jews were not able to fulfill God's Law perfectly. The sacrificial system was in place to provide forgiveness for those who failed to keep God's Law. The Gentiles lived in complete rebellion to the law that they had received. All of this points to the need for Christ.
The bottom line is we are all to be judged. If you place your faith in Jesus Christ, he will defend you to the father, as he payed for your punishment at the cross. If you try to defend yourself, your foolishness and rebellion will be silenced eternally. Place your faith in Christ Jesus.