A. From the word echod - one. Brothers are as one. Either in the sense of relationships or in the sense of doing Mitzvos.
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Q. How many types of people are there that are disqualified from serving as witnesses ?
A. 10. Rambam
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Q. May a convert serve as a witness ?
A. Yes.
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Q. How many places in Shas does the Halacha follow Reish Lokish ?
A. 3 places.
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