Anyway, simple Chana thought that meant the men actually wrote their wives a writ of divorce and from the time they went off to battle, poof! The women are all unmarried. But Heshy said it's actually not that way; there's a concept called למפרע which effectively ensures a retroactive get. Or as Heshy put it:
"Let's say the get was written at July 1st 2010 at 10pm. So Uriah writes, "If I don't return after the war is over, this get is effective as of this instant that I sign the get."
So let's think about that logically. When David and Bathsheba first sleep with one another, she is still technically married to Uriah. Then she finds out she is pregnant. David tries to have Uriah sleep with her but he won't hear of it. David then resorts to having Uriah killed. Since Uriah doesn't come home from the battle, the get retroactively becomes effective from the moment he first signed it. Because of that, Bathsheba was a magically unmarried woman at the time she slept with David.
Does that boggle anyone else's mind?
I'm curious about a practical application of this למפרע idea. Heshy said the same idea exists by Kiddushin. Therefore, a man can say as follows: "I am mekadesh you now on the condition that you don't eat chocolate for 30 days." If she ends up not eating chocolate after 30 days have passed, it is as though the kiddushin had gone into effect from the very moment the man had spoken, not at the end of the 30 days. Retroactive kiddushin, in other words.
So here's my question: We know that if a maiden is raped, there's a totally different penalty that occurs if she is betrothed and raped than if she is a maiden who is not betrothed. So let's say our girl, who is not eating chocolate for 30 days in order to accept the kiddushin, is raped on the 3rd day. Is she halakhically speaking a betrothed maiden or not? And if you say she is, doesn't that mean the kiddushin went into effect at precisely the moment at which he spoke (in which case it's not retroactive- it happened right then!) And if she's not, then aren't you saying the kiddushin only goes into effect after the 30 days? It seems to me you have to make a choice at some point. How can you just have this idea of time-travelling gittin? Or is there maybe a difference between kiddushin and when a maiden is meorasa?
So please explain and boy, am I jealous of you yeshiva guys. You learn such fascinating things!