What does the Bible say about salvation by works or by grace?

Salvation is a central theme throughout Scripture, particularly emphasized in Galatians. The Apostle Paul argues that the Galatians were tempted to trust in their works alongside Christ's work, which contradicts the essence of grace. Galatians 4:21-31 illustrates that salvation cannot coexist with a reliance on the law or human effort; rather, it is only through faith in Jesus Christ that we become children of promise, as exemplified by Isaac’s miraculous birth. Our hope rests in Christ's completed work that fully satisfies God's justice, rendering any attempt at works-based righteousness ineffective.