Sifrei on Deuteronomy
והיה כי יאמר אליך לא אצא מעמך. (קדושין כב) יכול פעם אחת? תלמוד לומר (שמות כא) ואם אמר יאמר העבד (אהבתי את אדוני), עד שיאמר וישנה.
(Devarim 15:16) "And it shall be, if he say to you: I shall not leave": I might think (that he says this) one time; it is, therefore, written (Shemoth 21:5) "And if the slave say, will say" — He must say it and repeat it.
(אם) אמר בתוך שש ולא אמר בסוף שש - הרי זה אינו נרצע, שנאמר לא אצא חפשי עד שיאמר בשעת יציאה. אמר בסוף שש ולא אמר בתוך שש - הרי זה אינו נרצע, שנא' ואם אמר יאמר העבד - עד שיאמר כשהוא עבד.
If he said it in the midst of the six years, but not at the end, his ear is not bored, it being written (Ibid.) "I shall not go out free" — It must be said at the time of going out. If he said it at the end of the six years, but not in their midst, his ear is not bored, it being written "And if the slave say, will say" — It must be said when he is a slave.
כי אהבך. מכלל שנאמר (שם) אהבתי את אדוני מכאן אתה אומר, היה הוא אוהב את רבו ורבו אינו אוהבו - הרי זה אינו נרצע, [שנאמר כי טוב לו עמך], עד שיהיה הוא אוהב את רבו, ורבו אוהבו. היה הוא אהוב על רבו והוא אינו אוהב את רבו, הרי זה [אינו] נרצע, שנאמר כי אהבך. לו אשה ובנים ולרבו אין אשה ובנים - אינו נרצע, שנאמר כי אהבך ואת ביתך.
(Ibid. 15:16) "because he loves you and your household": His saying (Shemoth, Ibid.) "I love my master, my wife, and my children" apprises us that his ear is not bored unless he has a wife and children. Whence is it derived (that his ear is not bored) unless his master has a wife and children? From "because he loves you and your household." From here it was ruled: If he had a wife and children and his master did not, or if his master had a wife and children and he did not, his ear is not bored. If his master loved him, but he did not love his master, his ear is not bored, it being written (Shemoth, Ibid.) "I love my master." If he loved his master, but his master did not love him, his ear is not bored, it being written (Devarim, Ibid.) "because it is good for him with you."
(אם) חלה הוא או רבו - אינו נרצע, שנאמר כי טוב לו עמך.
If he or his master took ill, his ear is not bored, it being written "because it is good for him."