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

The assurance of God's unbreakable promises stems from His nature; God is immutable and faithful. Scripture repeatedly illustrates that God does not lie (Titus 1:2) and that His covenants, particularly those associated with salvation, cannot be disannulled (Hebrews 6:18). His character as faithful guarantees that His promises to redeem and save His people will stand, exemplified in the eternal nature of the new covenant established through Christ. This aspect of His character reinforces the belief that all who are in Christ are eternally secure in their salvation, regardless of any outward failures.