number - Echad Ushloshim Umeya?

Who knows one hundred thirty-one?

Please cite/link your sources, if possible. At some point at least twenty-four hours from now, I will:

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  Upvote all interesting answers.

  
  
  


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  Accept the best answer.

  
  


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  Go on to the next number.

  
  

Answer

The first and last letters of the first four chapters of Tehillim add up to 131, which is also the numerical value of סמאל (the angel of evil). We therefore say these four chapters on Yom Kippur night, so that G-d save us from inadvertent uncleanness on this holy day.

(Pri Eitz Chaim, Yom Hakippurim 2)

Various later commentators point out that the sum of the relevant letters is actually only 126. Possible answers include:

• that we also add the ה of the word האיש (the second word of the first chapter);


• that we add the number of chapters themselves, plus one for the overall count (כולל);


• that we add the number of letters in the word בברית, which the Arizal says (and which R' Shneur Zalman cites in his siddur) as the vocalization of Hashem's name to have in mind while reciting these chapters.

(Shaar Hakollel 42:13)