Reference for Gittin 4:2

רבא אמר לפי שאין עדים מצויין לקיימו

Raba says: It is because it is not easy to find witnesses who can confirm the signatures.<span class="x" onmousemove="('comment',' In case the husband comes and questions the validity of the Get, and the declaration of the bearer is regarded as an authentication of the signatures by two witnesses. ');">²</span>

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