Gittin 43A

דלמא מודה ומיפטר.

Perhaps he will admit his obligation and become exempt from his obligation to pay, for one who admits that he is required to pay a penalty before the court obligates him to pay it is exempt.

ותבעי לרבנן ⁠– עד כאן לא קאמרי רבנן אין אדם מקנה דבר שלא בא לעולם ⁠– אלא כגון פירות דקל, דהשתא מיהא ליתנהו; אבל הכא ⁠– הא קאי שור והא קאי עבד. מאי?

And you could raise this dilemma according to the opinion of the Rabbis as well, as the Rabbis state that a person cannot transfer ownership of an entity that has not yet come into the world only in a case such as the produce of a date palm, which now, at least, is not in the world. However, here, the ox is standing and the slave is standing, and there is no need for any change in the reality. What is the halakha in this case?

אמר רבי אבא, תא שמע: ״ויליד בית״⁠ – מה תלמוד לומר? אם קנין כסף ⁠– אוכל, יליד בית ⁠– לא כל שכן?!

R' Abba said: Come and hear a proof based on a halakhic exposition of the verse that details those who may partake of teruma. The verse states: “But if a priest buys any person, the purchase of his money, he may eat of it; and those who are born in his house, they may eat of his bread” (Leviticus 22:11), and the rabbis expound as follows: What is the meaning when the verse states: “And those who are born in his house”? If a slave, who is the purchase of his money, may partake of teruma, then in the case of those slaves who are born to the priest in his house, is it not all the more so that they should be able to partake of teruma?