(Exodus 22:13) "And if a man borrow from his neighbor": Scripture "cuts off" a borrower from the class of "watcher," and treats it (as a class) in itself. "from his neighbor": We are hereby taught that he (the borrower) is not liable until he removes it from the lender's domain.
The Torah Draws a Sharp Legal Distinction Between Someone Who Watches
Mekhilta Tractate Nezikin 16:21