The talmud is discussing hazakah, adverse possession of property.
The general principle is that if you occupy somebody else's property
long enough and the owner doesn't protest, you can claim ownership.
The g'mara records a dispute about whether the owner has to make his
protest directly to the occupier (as opposed, say, to going to a court).
It records one argument that says that taking possession of a fugitive's
property does not confer hazakah, and this is because the fugitive
can't very well return to make his protest. But another says you
can possess a fugitive's property.
Another argument says that the reason we allow three years for the
objection if the owner is overseas is that we need to allow time for him
to first hear about it and then return; if he could make his protest from
where he is, we wouldn't need to allow time for him to return. Raba says
the law is that you do not need to protest in the presence of the occupier
(that part about returning from overseas is just good advice), because
"your friend has a friend and your friend's friend has a friend" -- in
other words, we're relying on the rumor mill to get word to the occupier
that the owner has protested.
And what is a valid protest? If he says "So-and-so is a robber", this
is not sufficient. If he says "So-and-so is a robber who has seized my
land wrongfully and I'm going to sue him tomorrow", that's a valid
protest. He must make this protest in front of either two or three
people (there's a dispute about that), and he must not bar them from
spreading the word. (38b-39a)
Originally posted at
http://cellio.dreamwidth.org/2017/03/02/bava-batra-39.html.
comments there. Reply there (preferred) or here.