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Hence a twofold justification flows: one in the legal covenant by one’s own righteousness according to the clause, “Do this and live”; the other in the covenant of grace, by another’s righteousness (Christ’s) imputed to us and apprehended by faith according to the clause, “Believe and thou shalt be saved.” Each demands a perfect righteousness. The former requires it in the man to be justified, but the latter admits the vicarious righteousness of a surety. The former could have place in a state of innocence, if Adam had remained in innocence. But because after sin it became impossible to man, we must fly to the other (i.e, the gospel), which is founded upon the righteousness of Christ.