Reference for Yevamot 45:7
ורבנן למעוטי שפחה ועובדת כוכבים מנא להו נפקא להו (שמות כא, ד) מהאשה וילדיה תהיה לאדוניה
On the contrary! A slave and a heathen should have been included since on embracing the Jewish faith, betrothal with himself is also valid! — When any of these adopts the Jewish faith she becomes a different person.<span class="x" onmousemove="('comment',' And is no longer regarded as a heathen or slave. ');"><sup>18</sup></span> Whence do the Rabbis deduce the exclusion of a slave and a heathen? — They deduce it from The wife and her children shall be her master's.<span class="x" onmousemove="('comment',' Ex. XXI, 4. ');"><sup>19</sup></span> And R. Jose son of R. Judah? — One text refers to a slave and the other to a heathen. And both are required; for had we been informed [concerning the exclusion of the] slave, it might have been thought [that this was so in her case] because she has no recognized ancestry, but not in that of a heathen who has recognized ancestry. And had we been informed [of the exclusion of the] heathen, it might have been assumed [that this was so In her case] because she stands under no obligation In relationship to the observance of commandments,<span class="x" onmousemove="('comment',' A heathen is under no obligation to observe the precepts of the Torah. ');"><sup>20</sup></span>