What does the Bible say about calling and election?

In 2 Peter 1:10, believers are encouraged to give diligence to make their calling and election sure, indicating that it is an important aspect of the Christian faith. The doctrine of election reveals that God, in His sovereignty, has chosen a people for Himself long before the foundation of the world. This choice is not based on any merit or intrinsic quality within those chosen, but rather it stems from His everlasting love and grace. The believer's assurance in their calling is founded in their understanding of God's faithfulness and His promises. Understanding calling and election reassures the believer that their salvation rests in God's sovereign purposes and not in their own efforts or abilities.