The Medrash tells us: “Before Avraham, old age is not found in the Torah, but of him it states: ‘Avraham was old.’ Before Yitzchok, suffering is not mentioned, but of him it says, ‘His eyes dimmed from sight.’ Before Yaakov, illness is not found, but of him it says, ‘Behold, your father is ill.’” Indeed, the Patriarchs persuaded Hashem, for the sake of mankind, to give man “gifts” - old age, suffering and disease! We need to understand what moved them to ask for these three things.

   R’ Zalman Sorotzkin zt"l (Oznaim L’Torah) explains that Avraham’s kindness brought him to the highest spiritual degree; not only feeling a traveler’s physical suffering due to hunger and strain, but also his mental anguish when, among strangers, he does not receive the honor and respect he is used to at home. Avraham, on the other hand, honored everyone, even Arabs “who worship the dust of their feet.” Thus, Avraham recognized a unique problem: With everyone looking exactly the same, when fathers arrived somewhere with their sons, no one could tell whom to honor more. He, therefore, asked Hashem to crown fathers with old age. 

   Yitzchok, cultivated the fear of Divine retribution. On two occasions he shuddered with fear: when he was bound by the Akeida and feared lest the sacrifice be flawed, and again when Esav approached him for a blessing, and he saw Gehinnom open beneath him. It was he who feared to die without suffering, lest that invite a stricter punishment in the afterlife. Thus, he asked for suffering to purge his “sins.”

   Yaakov saw that Avraham had produced a Yishmael, and Yitzchok, an Esav. Thus, he successfully devoted his whole life to educating his children in Torah and mitzvos. All the same, he feared that his sons might leave the correct path before his death. Knowing that children will always heed a father’s last request before death, he asked Hashem to inform mankind, through illness, that a person’s death is not far off, so that “during two or three days of illness he can bring his children back to the right path.” (Medrash)