Calvin saw the testimony of Christian martyrs as a firm proof for the credibility of Scripture.
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Now with what assurance ought we to enlist under that doctrine which we see confirmed and attested to by the blood of so many holy men! They, having once received it, did not hesitate, courageously and intrepidly, and even with great eagerness, to suffer death for it. Should we not accept with sure and unshaken conviction what has been handed on to us with such a pledge? It is no moderate approbation of Scripture that it has been sealed by the blood of so many witnesses, especially when we reflect that they died to render testimony to the faith; not with fanatic excess . . . but with a firm and constant, yet sober, zeal towards God.” John Calvin, Institutes I, page 92
