The father of Reb Meir Premishlaner zt'l saw a vision in a dream. He saw heaven calling young people "old" and old people "young," and he asked them why they do so. Heaven explained, "Here we view people according to how long they serve Hashem. We don't look at the age they lived. We measure them according to the amount of time they served Hashem."
A similar story is told about a person who came to a cemetery, and he read on one grave, "Here lies a person who was niftar at the age of two." Another grave says, "Here lies the rav who was niftar at seven years." There wasn't anyone in the graveyard who had lived more than ten years. He asked, "What happened in this city? Was there an epidemic, and everyone died young?" Most people didn't know the answer, but after asking around enough, he found an old person who supplied the explanation. "In this city, they didn't write the number of years one lived. They wrote on the tombstone the number of years one served Hashem because only those are considered years of life. Some lived until eighty years or more, but on the tombstone, they wrote that he lived a few years because that was how long they served Hashem."
The hint is from the pasuk ימים שנתיים מקץ ויהי. Sometimes, from שנתיים years of life, all that was used was ימים, a few days’ worth of time in Hashem's service.
Pharaoh asked Yaakov how old he was, and he replied (47:9) שנה ומאת שלשים מגורי שני ימי חיי שני ימי היו ורעים מעט, "The days of the years of my sojourning are one hundred thirty years. The days of the years of my life have been few and miserable."
The Malbim explains that Yaakov told Pharaoh that the years of one's life can be divided into two categories. One category is the number of years that one lives. About those years, Yaakov said that he lived 130 years. He called those years מגורי שני, the years he lived on earth, but they weren't חיי שני, the years of his life, for the years of his life are the years in which he served Hashem. About חיי שנות, the true years of one's life, Yaakov humbly said that they were מעט, few years, ורעים. (Take note of Yaakov Avinu's humility. The Torah testifies that Yaakov was (Bereishis 25:27) אֹה ָלִים ישֵׁב ת ָּם אִישׁ, always sitting in the beis medresh, studying Torah. For fourteen years, he studied in the yeshiva of Shem v'Ever. Throughout those years, he didn't sleep at night, not once. He was always studying Torah. Nevertheless, he said חיי שני ימי היו ורעים מעט, "The days of the years of my life have been few and miserable.")
