How do we know that salvation is secured through Christ?

Salvation is secured through Christ as affirmed in Matthew 1:21, which proclaims that He shall save His people from their sins. This means that His mission was decisive, not merely to propose a way to salvation but to accomplish it fully. The sermon outlines that when Jesus proclaimed from the cross, 'It is finished,' He definitively completed the work of atonement and there remains nothing left for believers to contribute towards their salvation. Hence, the certainty of salvation is founded on the completed work of Christ, who will decisively save all whom the Father has given Him.