Why is the concept of imputed righteousness important in Reformed theology?

In Reformed theology, the doctrine of imputed righteousness is central to understanding salvation. This means that upon faith in Jesus Christ, His perfect righteousness is credited to the believer, allowing them to stand justified before a holy God. This concept underscores the grace of God in salvation, as it emphasizes that righteousness is not something earned through human effort but a divine gift imparted to those chosen in Christ. As highlighted in Romans and Revelation, such righteousness is essential for entry into heaven and the comfort believers derive from knowing that they are united with Christ and his righteousness, giving them assurance of eternal life.