Why is the concept of grace significant in Christianity?

Grace is the cornerstone of Christian faith, recognized as unmerited favor extended to sinners. Ephesians 2:8-9 emphasizes that salvation is by grace through faith, not works, highlighting that it is solely the work of God in our lives. This grace not only justifies believers but also sustains them spiritually as they grow in faith and obedience. Understanding grace transforms the believer's approach to God and to life, fostering a spirit of gratitude and enabling a life lived in worship and service to Christ.