How do we know that God's promises are everlasting?

God's promises, including the everlasting covenant, are rooted in His unchanging character and are not contingent upon human faithfulness, as seen in the contrast between the covenant with Israel and the everlasting covenant made before the foundation of the world among the Father, Son, and Holy Spirit. The Old Testament covenants were based on condition and often broken by people, while the new covenant promises forgiveness and transformation, ensuring that God's elect will be brought to Himself. Passages such as Romans 8:28-30 emphasize that God's purpose will prevail and that His elect will ultimately be gathered.