Even if we have accepted Jesus Christ as our Lord and Savior, we are still obliged to follow the commandments to unite our freewill with God's grace.
St. John 15:10: "If you keep my commandment, you will remain in my love as I have kept my Father’s commandment and remain in his love"
The grace of GOd INCLUDES freewill as a gift, and once we have Faith we retain our freewill. We still have the choice to do good or bad. God is so generous to have given us complete freedom, but God also demands that we OBEY him.
Classic example: Adam and Eve, who were under the perfect grace of God, still sinned because of their God-given freewill. Despite being in the state of perfect grace of faith in God, they chose to disobey God's commandment and therefore were banished from the Garden. It is God's desire to perform the commandments.
False "gospel of grace" common in protestant churches preaches the pre-forgiveness of sin in virtue of Christ's sacrifice on the cross: They say "Enjoy the sin because you’re born to reign, you’re already forgiven", but to keep the faith. However, the Bible CONDEMNS sin.
1 Corinthians 6:9-10
Or do you not know that the unrighteous will not inherit the kingdom of God? Do not be deceived: neither the sexually immoral, nor idolaters, nor adulterers, nor men who practice homosexuality, nor thieves, nor the greedy, nor drunkards, nor revilers, nor swindlers will inherit the kingdom of God.
In the end, God calls us to a life of faith and holiness by keeping the commandments as preached by the Catholic Church for 2 millenia:
Revelation 14:12: Here is the patience of the saints: here are they that keep the commandments of God, and the faith of Jesus.
See link:
FALSE GOSPEL OF GRACE