Interesting question. Though many commentators deny that this refers to a lifespan limit (e.g. Gill and Jameison, Fausset & Brown), a number of modern exegetes consider it to be so. The New Jerusalem Bible renders the verse:
Calvin's commentary holds to the "old line," but observes that there is a consequent discrepancy to explain:
?Yet his days shall be one hundred and twenty years.?
Certain writers of antiquity, such as Lactantius, and others, have too grossly blundered in thinking that the term of human life was limited within this space of time; whereas, it is evident, that the language used in this place refers not to the private life of any one, but to a time of repentance to be granted to the whole world. Moreover, here also the admirable benignity of God is apparent, in that he, though wearied with the wickedness of men, yet postpones the execution of extreme vengeance for more than a century. But here arises an apparent discrepancy. For Noah departed this life when he had completed nine hundred and fifty years. It is however said that he lived from the time of the deluge three hundred and fifty years. Therefore, on the day he entered the ark he was six hundred years old. Where then will the twenty years be found? The Jews answer, that these years were cut off in consequence of the increasing wickedness of men. But there is no need of that subterfuge; when the Scripture speaks of the five hundredth year of his age, it does not affirm, that he had actually reached that point. And this mode of speaking, which takes into account the beginning of a period, as well as its end, is very common. Therefore, inasmuch as the greater part of the fifth century of his life was passed, so that he was nearly five hundred years old, he is said to have been of that age.
Footnote
{4} The whole of this passage might have been more clearly expressed. At the close of chapter 5, it is said, ?Noah was five hundred years old: and Noah begat Shem, Ham, and Japeth.? In the verse on which Calvin here comments, it is stated, that man?s days on earth ?shall be one hundred and twenty years?; but in Genesis 7:11, we are told, that the deluge came ?in the six hundredth year of Noah?s life.? This would pare down the one hundred and twenty years to one hundred; and therefore Calvin asks, ?Where are the remaining twenty to be found?? To answer this question, he shows that there was something indefinite in the statement of Noah?s age in the first of these passages, and Moses does not say that the flood began precisely in that year. He therefore concludes that, according to a common mode of speaking among the Hebrews, he was in the fifth century of his life; and therefore he would infer, that Noah was about four hundred and eighty years of age at the time referred to: if one hundred and twenty years be added, it will make him six hundred years old at the time of his entering the ark. ?Ed.
