Christ fulfills the law for believers by perfectly obeying it and bearing its penalty, granting righteousness to those who are in Him.
Romans 8:3 states that 'what the law could not do, in that it was weak through the flesh, God sending His own Son... condemned sin in the flesh.' This illustrates that the law, while good and holy, cannot save due to human weakness. Christ's coming as a man and His perfect obedience fully satisfied the requirements of the law. Through His atonement, He not only upholds the law but imputes His righteousness to believers, thus declaring them justified. This dual aspect of fulfilling the law—obedience and punishment—ensures that those who are in Christ are seen as righteous before God.
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