Reference for Shabbat 115:7

גופא אמר שמואל יוצא העבד בחותם שבצוארו אבל לא בחותם שבכסותו תניא נמי הכי יוצא העבד בחותם שבצוארו אבל לא בחותם שבכסותו

It was stated above: 'Samuel said: A slave may go out with a seal around his neck, but not with the seal on his garments.' It was taught likewise: A slave may go out with a seal around his neck, but not with the seal on his garments. But the following contradicts this: A slave may not go out with the seal around his neck, nor with the seal on his garments; and neither are susceptible to defilement.<span class="x" onmousemove="('comment',' Because they are neither ornaments nor useful utensils, but merely badges of shame. ');">⁷</span>

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