The covenant is sure because it is based on God's promises and His immutable nature, fulfilled through Christ.
We can trust in the surety of God's covenant because it is established on His eternal nature and His promises, which are unchangeable. Hebrews 6:13-18 emphasizes that God's promises are confirmed by an oath, providing us with strong consolation. God cannot lie, and thus the covenant of grace, which assures us of salvation, stands firm in Christ. As the text mentions, this covenant is ordered in all things and is not dependent on human efforts but on the perfect fulfillment of Christ. The assurance that God will never turn away from His promises provides believers with hope and confidence.
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