God's promises will not fail because they are based on His unchanging nature and depend solely on Christ's finished work.
The assurance that God's promises will not fail is rooted in His sovereignty and unchanging character. Scripture emphasizes that God works all things according to the counsel of His will (Ephesians 1:11). In the new covenant, God's promises are fulfilled in Christ, who is the surety of our salvation. As Paul writes in 2 Corinthians 1:20, all the promises of God are 'Yes' in Christ, indicating that His work cannot fail. When we look to Him and His righteousness, we find peace and certainty that no one chosen by God will perish; they will be preserved and glorified according to His purpose.
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