What does the Bible say about being under law vs grace?

In Hebrews 12, the Apostle Paul presents a contrast between Mount Sinai, representing the law, and Mount Zion, representing grace. He explains that the Israelites were fearful and unable to endure the demands of the law, which required absolute perfection. Conversely, through grace, believers come to Mount Zion, the city of the living God, where they are offered forgiveness and righteousness through Jesus Christ. The emphasis is on the unmerited favor of God that saves us, which is foundational to the gospel.