The Rogochover further explains that there is a machlokes between the Rambam and Ramban if a woman appoints a שליח to accept the קידושין and the husband writes a שטר, if this שטר must be written with the knowledge [מדעת] of the שליח [Rambam] or the knowledge of the woman [Ramban]. The Rambam holds that the status of of שליח applies immediately when the שליח starts going in the שליחות of the sender. Since he is already a שליח from the get-go, it is sufficient that the שטר be written מדעתו. The Ramban holds that his status as a שליח begins only when the קידושין is given and not before
"וא"כ צריך שיהיה מתחילה קידושין דהיינו שיהיה מתחילה נכתב לדעתה".
First it must be written מדעת האשה because at this stage there is not yet קידושין and only when there is actual קידושין is the שליח a שליח. Therefore it doesn't help to write the שטר with the דעת השליח because he is not yet a שליח!!
In other words, this is the Rambam being consistent with his opinion that שליחות is a דין כללי that applies to the whole Torah and thus begins from the time of appointment and we don't require an act of קידושין. While the Ramban holds that it is a דין פרטי that is unique to קידושין and thus begins only with the act of קידושין and not before.
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In other words, this is the Rambam being consistent with his opinion that שליחות is a דין כללי that applies to the whole Torah and thus begins from the time of appointment and we don't require an act of קידושין. While the Ramban holds that it is a דין פרטי that is unique to קידושין and thus begins only with the act of קידושין and not before.
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