Gittin 2B

לפי שאין בקיאין לשמה.

It is because the people who live overseas are not experts in writing a bill of divorce for her sake. It is not sufficient for a bill of divorce to be written in a technically correct manner. It must also be written for the sake of the man and the woman who are divorcing. Therefore, when the witness comes before the court and says that it was written and signed in his presence, he is testifying that the writing and the signing of the bill of divorce were performed for the sake of the man and woman in question.

רבא אמר: לפי שאין עדים מצויין לקיימו.

Rava says a different reason: It is because there are no witnesses available to ratify it. Since the bill of divorce was written in a distant place, it is possible that the husband, or someone else, might later claim that the bill of divorce is a forgery. For this reason the agent must say that the bill of divorce was written and signed in his presence, a declaration that bars any subsequent objection on the part of the husband.

מאי בינייהו? איכא בינייהו דאתיוהו בי תרי. אי נמי, ממדינה למדינה בארץ ישראל.

The Talmud asks: What is the difference between these two explanations? The Talmud answers: There is a difference between them with regard to a case where two people brought the bill of divorce. In this case, two witnesses are available to ratify the bill of divorce if someone objects to its validity. Alternatively, the difference concerns a case where the agent brings the bill of divorce from one region to another region within Eretz Yisrael. Here there is no concern that the bill of divorce might not have been written for her sake, as the residents of Eretz Yisrael are aware of this requirement. However, witnesses are not necessarily available to confirm the document.