Keilim28: 1
שָׁלֹשׁ עַל שָׁלֹשׁ שֶׁנְּתָנָהּ בַּכַּדּוּר, אוֹ שֶׁעֲשָׂאָהּ כַּדּוּר בִּפְנֵי עַצְמָהּ — טְהוֹרָה. אֲבָל שְׁלֹשָׁה עַל שְׁלֹשָׁה שֶׁנְּתָנוֹ בַכַּדּוּר — טָמֵא. עֲשָׂאוֹ כַדּוּר בִּפְנֵי עַצְמוֹ — טָהוֹר, מִפְּנֵי שֶׁהַתֶּפֶר מְמַעֲטוֹ.
[A piece of cloth measuring] three [fingerbreadths] by three [fingerbreadths] that was placed inside a ball, or it itself was made into a ball, it is tahor. But [a piece of cloth measuring] three [handbreadths] by three [handbreadths] that was placed inside a ball is tamei. [If] it itself was made into a ball, it is tahor, since the stitching diminishes it.