How does the grace of God relate to righteousness?

In Galatians 2:21, Paul firmly states, 'I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain.' This profound assertion illustrates that if salvation could be earned through adherence to the law, then Christ's sacrificial death would be meaningless. God's grace is the unmerited favor bestowed upon sinners, allowing them to attain righteousness through faith in Christ. Understanding grace is crucial for Christians, as it emphasizes that salvation is entirely a work of God, dispelling any notion of self-reliance or merit.