After Yaakov Avinu arrives in Egypt, Yosef takes his father and introduces him to Pharaoh, who inquires as to the patriarch's age. Yaakov's response strikes us as somewhat peculiar: "Yaakov answered Pharaoh, 'The years of my dwelling are one hundred and thirty. Few and hard have been the years of my life, and they do not come up to the life spans of my fathers during their days of dwelling'" (47:9). Why doesn't Yaakov simply answer the king's question? Why does he bemoan his difficult life rather than simply telling Pharaoh his age? Indeed, one Midrashic passage, cited by the Chizkuni and other Ba'alei Tosefot (see Da'at Zekeinim), criticizes Yaakov Avinu for complaining about his life (as we discussed in a S.A.L.T. two years ago).
Many commentators, however, seek to justify and explain Yaakov's comments. One approach, adopted by the Ramban, Rashbam and Chizkuni, claims that Pharaoh inquired about Yaakov's age because he looked exceedingly old. Unaccustomed to meeting people wearing such an aged appearance, Pharaoh was curious to know just how old Yaakov was. The patriarch replied that in fact he has not yet reached exceedingly old age (a life span of one hundred and thirty years was still common at that time), but his crisis-ridden life, the anxiety, fear, hard work, and sorrow he had suffered during his relatively short life has made him look old.
Seforno explains much differently, taking a closer look at the text and distinguishing between two terms: "yemei chayai" ("the days of my life") and "yemei megurai" ("the days of my dwelling"). A careful reading of Pharaoh's question reveals that he asks Yaakov specifically about "yemei shenei chayekha" - the days of the years of your life. Yaakov, however, replies that "yemei shenei megurai" - the days of the years of my dwelling - number one hundred and thirty.
Seforno claims that "megurai" denotes physical existence itself, whereas "chayai" refers to a certain quality of existence, a life of tranquillity and happiness. Yaakov tells Pharaoh that although he has physically lived for one hundred and thirty years, much of that period cannot be described as "chayai" - a life of peace and happiness. His forefathers, by contrast, enjoyed this quality of life ("shenei chayei avotai") over the course of their lifetime ("bi-mei megureihem"); although they, too, experienced the hardships of exile, they did not endure the ongoing struggles that Yaakov encountered.
Thus, Yaakov responds as he does for purposes of clarification; Pharaoh had inquired about "yemei shenei chayekha," so Yaakov finds it necessary to draw this distinction between "shenei chayai" and "shenei megurai."
Rav Shimshon Refael Hirsch likewise distinguishes between these two terms, only in a different direction. He claims that the difference involves not stability and tranquillity, but rather the religious and spiritual dimension of life. Whereas "megurai" denotes simply physical existence, "chayai" describes an existence characterized by spiritual achievement, the fulfillment of one's religious responsibilities and the realization of his potential.
Pharaoh inquired as to "shenei chayekha," but Yaakov clarifies that this is not the correct question. He understood that Pharaoh asked about his age, not about his religious achievement. He therefore informs the king of "shenei megurai" - his years of physical existence, and then humbly laments what he perceives as his all too few years of "shenei chayai," of spiritual achievement. He confesses to having fell short of the accomplishments of his predecessors, of having failed to transform all his years from "shenei megurai" - mere physical existence - into "shenei chayai" - an existence rich in spiritual meaning and achievement.