See today's Shtikel at
http://limudtorah.jewishweb.org/index.php?option=com_co...=view&id=24&Itemid=1

I would answer as follows:

There is a difference if the woman was the actual person that the Torah saaid the Asei must be done with. Like by Yibum. The Mitzva has to be done with only that woman. Thus the Asei is that Reuvain must do Biya with Rachel. Thus her Biya is explicitly part of the Asei, so it's part of the sanctioned act and she may do it even if it wasn't her Asei

But if the Asei is not particularly on her. Like the half Eved case where he can do his Asei with anyone else. Thus she's not explicitly in the Asei. Therefore she can't do it even though it would help someone else do a Mitzvah.

I'm sorry, i made a mistake. This was not for tonight's piece, but for tomorrows. sometimes I make the worst mistakes. Well here is the answer, try to figure out the question. I guess it's like Jepordy!

Aha!! The moment we were all waiting for. The real post is on tonight at
http://limudtorah.jewishweb.org/index.php?option=com_co...view&id=25&Itemid=27

So basically, how do we reconcile Tosfos saying that a woman can't help a half Eved to have children since she doesn't have a Mitzva to have children, yet a Yivama that's a Lav may be Miyabem form the Torah with the Yuvum even though the Mitzva is exclusivly on him?

So I would answer as follows:

There is a difference if the woman was the actual person that the Torah saaid the Asei must be done with. Like by Yibum. The Mitzva has to be done with only that woman. Thus the Asei is that Reuvain must do Biya with Rachel. Thus her Biya is explicitly part of the Asei, so it's part of the sanctioned act and she may do it even if it wasn't her Asei

But if the Asei is not particularly on her. Like the half Eved case where he can do his Asei with anyone else. Thus she's not explicitly in the Asei. Therefore she can't do it even though it would help someone else do a Mitzvah.

Tune in Moitze Shabbos how the Minchas Chinuch himself learnt.