How does God's promise provide assurance for believers?

In Hebrews 6:13-18, the assurance of God's promises is emphasized through His covenant and the oath He made to Abraham. Since God cannot lie, His promises are secure and serve as a firm foundation for our faith and hope. The sermon illustrates that God's eternal counsel and His oath constitute two immutable things that give believers consolation. This divine promise reaffirms that God's purpose of salvation is not dependent on human effort but rests entirely on His grace and faithfulness, ensuring that all who believe in Christ will be eternally secure.