Reference for Shabbat 129:16

לא שביק להו יוצאות בחוטין והאנן תנן הבנות יוצאות בחוטין בנתיה דאבוה דשמואל דצבעונין הוו

Said Abaye: This proves that all [these things] are beneficial for it.<span class="x" onmousemove="('comment',' Viz., the hardness, corrosion, and the figure, and only a coin possesses all three. ');">²⁶</span> YOUNG GIRLS MAY GO OUT WITH THREADS. Samuel's father did not permit his daughters to go out with threads, nor to sleep together; and he made mikwa'oth<span class="x" onmousemove="('comment',' Mikweh, pl. mikwa'oth, ritual bath. ');">²⁷</span>

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