Reference for Menachot 58:14

אמר רב יוסף הני תרתי מילי אמר רב בספרים ותניא תיובתיה חדא הא דאמר רב ס"ת שיש בו שתי טעיות בכל דף ודף יתקן שלש יגנז

If a man comes to purify himself, they assist him; but if he comes to defile himself, they open the door for him. And wherefore has [the letter he] a coronet? - Because the Holy One, blessed be He, says, If a man repents I will set a crown upon him. And why was the future world created with the letter yod? - Because the righteous men therein are but few.<span class="x" onmousemove="('comment',' The letter yod is the smallest letter of the alphabet, and in shape its head droops downwards.');">²²</span>

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