Numbers 26:63

63.These are they that were numbered. The former registration was made by Aaron. The difference between the two census is therefore specified, in order that Moses may take occasion to commemorate God’s judgment, which can never be sufficiently considered, that of 600,000, only two were found who had survived to the term prescribed by God. If any should object that the greater part would have died naturally, since they had arrived at their thirtieth: fortieth, and even fiftieth year, (198) and thus would have been some eighty years old before the completion of the forty years, I admit that such is the case; but many had not yet reached their twenty-fourth year. Nor can we doubt but that not a few of them were younger than Caleb and Joshua, whom we know to have been not only alive and well, but even strong and vigorous for many years afterwards. At any rate, therefore, not old age, but God’s vengeance, cut off half of them by an untimely death, as if he had openly put forth his hand from heaven and smitten them. It is not without reason, then, that Moses states that they were dead, as God had pronounced; not merely that by the punishment inflicted upon them he may inculcate upon us the fear of God, but also that we may learn to be aroused in earnest by his threats.