Who shall bring any charge against God's elect? It is God who justifies.  Who is to condemn? Christ Jesus is the one who died—more than that, who was raised—who is at the right hand of God, who indeed is interceding for us. (ESV)
This verse causes us to picture a court room scene. We are accused of being sinners. We are in violation of God's Law. This could be terrifying. However, we have an advantage in this situation. We are already declared innocent by the judge. God the Father has sent his son to pay the penalty for all of the sins that we are accused of. Verdict? Not guilty.
Let's consider who would actually bring the charges against believers in Jesus Christ. At the time that Paul wrote this letter to the church at Rome the likely people to bring accusation would have been the Jews. Many of the Jews had spent their lives painfully trying to keep the Law. The idea that Gentiles could jump in front of them and be declared innocent before God did not seem fair.
Who else could condemn us? Sadly, there are those who are fellow believers in Jesus Christ who are much too eager to condemn us. Condemnation is not a spiritual gift. We may see another believer who is struggling with a particular sin. Our response should not be to condemn them, but rather pray for them and also pray that we ourselves do not fall into the same sin.
The other one who will condemn us is Satan himself. Revelation 12:10 describes the final demise of our enemy. Listen to how he is described: "And I heard a loud voice in heaven, saying, “Now the salvation and the power and the kingdom of our God and the authority of his Christ have come, for the accuser of our brothers has been thrown down, who accuses them day and night before our God."
The Jews had no case against Gentile Christians. Your "brother in Christ" has no case against you. Satan himself has no case against you. If you belong to Jesus Christ no charge can be brought against you. Christ Jesus is always interceding for you. What a Savior!