Moses says that the waters of the flood decreased up to the tenth month: not that the decrease of the waters was then entirely finished (since a little below Moses said that in the six hundred and first year, in the first month, on the first day of the month, the waters were lessened upon the earth); but [the meaning is that], whereas before the tenth month (although the waters had decreased for many days) they nevertheless still covered the whole earth, even above all the mountains, then first — that is, at the beginning of the tenth month — the waters were so far diminished that the tops of the mountains too began to stand out and appear.¹

Cajetan computes this tenth month from the beginning of the flood, and judges that from the day on which the Ark rested (that is, from the seventeenth day of the seventh month) up to the first day of the tenth month, on which the tops of the mountains first appeared, seventy days passed: namely, the Flood had covered the mountains so deeply that, after it began to decrease, seventy days of its decrease passed before the peaks of the highest mountains, stripped of waters, appeared. Hear Cajetan: “‘The waters,’ he says, ‘were going and decreasing up to the tenth month’ — without doubt from the beginning of the flood. Seventy days, therefore, are described as having passed from the rest of the Ark upon the mountains up to the tenth month. For there flowed twelve days of the seventh month and fifty-eight days making up the eighth and ninth month: and on the day immediately following the aforesaid seventy days, the tops — or (what the Hebrew word signifies) the heads — of the mountains are said to have appeared. Therefore, when the Ark rested upon the mountains, the heads of the mountains were still so deeply covered with waters, that a space of seventy days was needed for them to be uncovered from the waters, and the whole Ark to be free of the waters — [the Ark] which, during those seventy days, was for no small part girt with the waters gradually failing. Nor does it stand in the way that in Hebrew it is said that the heads of the mountains ‘were seen.’ For it is not signified that they were actually seen by anyone, but that they were uncovered and stripped of waters — wherefore they became visible and conspicuous, such as they were not before, [being] covered with waters.” Thus far from Cajetan.²

But that Cajetan's opinion is not probable, one may argue in this way: If this tenth month is computed from the beginning of the flood, since before the beginning of the flood one month and sixteen days of the six hundredth year had passed, then the tops of the mountains would have appeared on the eighteenth day of the eleventh month of the six hundredth year, and there would remain, to complete that year, one whole month and besides twelve days — that is, forty-two days. But Moses, after the appearance of the mountains up to the beginning of the six hundred and first year, reckons first forty days, then twice seven days (which joined to them make fifty-four), after which he begins the six hundred and first year, saying that on the first day of the six hundred and first year Noah opened the covering of the Ark: but according to Cajetan's foregoing computation, this would have been done not on the first day, but on the thirteenth day of the six hundred and first year. Besides, Noah would not have gone out of the Ark in the six hundred and first year, in the second month, on the twenty-seventh day (as Moses narrates), but in the third month and on the twelfth day — which from the things said above it will be easy for the reader to gather.³

Besides, it would follow that Noah was in the Ark not only one whole Solar year (as almost all think), but, beyond one Solar year, remained in the Ark two months and ten days. Therefore that tenth month is not to be computed from the beginning of the flood, but from the beginning of the six hundredth year: just as was also said a little above about the seventh month in which the Ark rested. Wherefore, between the twenty-seventh day of the seventh month on which the Ark rested, and the first day of the tenth month on which the tops of the mountains appeared, sixty-three days intervened.⁴

But on the same words of Moses, by which it is said that on the first day of the tenth month the tops of the mountains first appeared, an arduous question arises in this place. For Moses says that on the first day of the tenth month the tops of the mountains appeared: thence he counts forty days, after which days Noah, opening the window, sent out the raven and the dove; and after these he reckons twice seven days, during which he sent out the dove twice. And all these days indeed make up the number of fifty-four days. After this Moses subjoins that in the six hundred and first year, in the first month and on the first day of the month, the earth was dried: but from the first day of the tenth month of the six hundredth year up to the first day of the first month of the six hundred and first year, three Lunar months passed — that is, not fifty-four days (as Moses indicates), but eighty-eight. The narrative of Moses, therefore, does not agree with itself in chronology; nay rather, it plainly destroys itself.⁵

Cajetan, who (as we said above) separates those forty days of rain from the other hundred and fifty during which the flood stood, and begins the seventh and tenth months named by Moses from the beginning of the flood, now says: that when Moses wrote that in the six hundred and first year, in the first month and on the first day, the earth was dried, he signified that there was then completed…⁶

…that the six hundredth year of Noah was then completed entire. For all the days of this year Moses numbered by parts: for first he mentioned forty-six days, when he said that Noah entered the Ark in the six hundredth year, in the second month, on the seventeenth day; then he reckoned forty days of rain; and after these he mentioned another hundred and fifty days, up to the diminution of the waters; to these another seventy, namely from the seventeenth day of the seventh month up to the first day of the tenth month; and besides these he named forty days, and moreover another twice-seven days: and from all the aforesaid days there is made up a sum of three hundred and sixty days, assigning to each Lunar month twenty-nine days.⁷

Now the year, among the ancients, consisted of three hundred and sixty days, according to the number of the degrees of the signs in the Zodiac, assigning one day to each degree: and such was the solar year among the Greeks and Romans, and (as is believed) also among the Egyptians; and that it was the same in the time of Moses and Noah may be gathered from this Chronology of the flood. But because the Sun does not complete its course before three hundred and sixty-five days and a quarter, in order that the year might agree with the motion of the Sun, thirty days were assigned to each of the months of the year, and every sixth year they added an intercalary month, to supply those five days which were in excess for the individual months. But this reckoning of the year and of intercalation Julius Caesar corrected, and described and established it as it now is. But into that year of the flood no intercalary month fell: wherefore that year had only three hundred and sixty days. And such, then, is Cajetan's opinion.⁸

But in this opinion and interpretation of Cajetan many things are by no means to be approved. First, Cajetan separates the forty days of rain from the other hundred and fifty: but that they ought not to be separated, we showed above is more probable. Then he computes the seventh and tenth months from the beginning of the flood: but that this too is less probable was said a little above. He assigns, besides, to each Lunar month only twenty-nine days: whereas one ought to assign twenty-nine and, besides, half a day; nay rather, according to Cajetan himself (assigning only twenty-nine days to each Lunar month), it would be necessary that a year composed of twelve Lunar months should consist of only three hundred and forty-eight days — which, however, he makes to be of three hundred and sixty days.⁹

Besides, what Cajetan said — that among the ancient Romans, Greeks, and Egyptians the year was of three hundred and sixty days, and that every sixth year one month was wont to be intercalated, and that this reckoning of the year was in use in the time of Noah, and is reckoned up by Moses in this place in the history of the flood — has somewhat of truth, but more of falsity. For Censorinus, in the book On the Birthday [of the Romans], writing about the reckoning of the year among various nations: “He by no means seems to err,” he says, “who accommodated the civil months to the course of the Moon — as most in Greece, among whom alternate months were made of thirty days. The Romans of old too imitated the same, when they had a year of three hundred and sixty days.” But in Macrobius it is thus [stated]…¹⁰

…“The Egyptians have all their months of thirty days, [and] have a year of only three hundred and sixty days; hence, their twelve months being unfolded (that is, three hundred and sixty days being completed), between August and September (or, as it is said in the Egyptian manner, between Mesori and Thoth, namely the last month of the year and the first of the following) they insert into the year the remaining five days of the solar circuit; and every fourth year, besides, they attach in the same place an intercalary day, which is made up from the quarters.” Thus in Macrobius.¹¹

Consonant with Macrobius write Herodotus, Diodorus, and Strabo. “Of all men,” says Herodotus, “it is agreed that the Egyptians first discovered the year, distinguishing it into twelve months of seasons: and that they discovered this from the stars, doing this (as it seems to me) more skillfully than the Greeks, because the Greeks every third year introduce an intercalary month for the sake of the seasons; but the Egyptians, reckoning each month at thirty days, add to this number five days every year: whence their reckoning of the cycle of the seasons holds, returning to the same point.”¹²

Diodorus Siculus relates that the same was observed by the Thebans, writing in this manner: “The Thebans profess themselves the most ancient of men, and that philosophy and Astronomy were first discovered by them, and that they were aided by the situation of their region for knowing the risings and settings of the motions of the stars; and that months and years were instituted by them. And they measured the days not according to the Moon, but according to the Sun, making a month of thirty days. And adding five days and a quarter of a day to the twelve months, they complete the course of the year; they do not interpose intercalary months, nor subtract days, as do some of the Greeks too.” Thus far from Diodorus.¹³

From these things it appears that among the ancient Egyptians the year was of three hundred and sixty-five days: although the last five days were not counted by them as parts [of the months], but were reckoned as added. It is not true, therefore, what Cajetan said — that the year in the time of Noah was of three hundred and sixty days, such, namely, as it was among the ancient Egyptians. What of this: that the Hebrews used Lunar years (each year, namely, of three hundred and fifty-four days), but nevertheless brought them back and accommodated them to the reckoning of the sun's motion, intercalating one month about every third year?¹⁴

To the question, therefore, and difficulty set above, it must be answered otherwise. To me, indeed, it seems very probable that Moses, in this history of the flood, did not number all the months [and] days of that year in which the flood occurred, but, passing over many in silence, enumerated only those on which something happened, or was done by Noah, which was notable and memorable, and contributed to illustrating this history of the flood. He named the seventeenth day of the second month: because on that day the flood began. He reckoned the forty days of rain: whence the increase of the flood came about. He mentioned the hundred and fifty days: because during them the flood stood, and after them the waters of the flood began to diminish. He named the twenty-seventh day of the seventh month: because then first the Ark settled upon the mountains. He made mention of the first day of the tenth month: because on that day the tops of the mountains first appeared. After this he reckoned forty days: because, those being passed, Noah, opening the window of the Ark, sent out the raven and the dove to explore whether the flood had ceased. He then added fourteen days, in which the dove, returning the first time to the Ark, brought in its mouth a branch of olive with green leaves; but, sent out again and yet not returning, gave a sign that the earth was now dried of the waters. But because on other days and months nothing similar to these (that is, nothing memorable) had happened, therefore Moses thought that those times were not to be reckoned up.¹⁵