Antinomianism literally means "anti-lawism." It denies or downplays the significance of God's law in the life of the believer. It is the opposite of the twin heresy, legalism - RC Sproul

There is an old rhyme that serves as something of an antinomian theme song. Its says,

"Freed from the law,
Oh blessed condition;
I can sin all I want,
and still have remission."

Antinomianism literally means "anti-lawism." It denies or downplays the significance of God's law in the life of the believer. It is the opposite of the twin heresy, legalism...

Antinomianism's primary error is confusing justification with sanctification. We are justified by faith alone, apart from works. However, all believers grow in faith by keeping God's holy commands - not to gain God's favor, but out of loving gratitude for the grace already bestowed on them through the work of Christ.

- R. C. Sproul, Essential Truths of the Christian Faith