daf bit: Bava Metzia 94

[cellio]

The mishna teaches: if a man borrows a cow and borrows or hires its owner with it (i.e. the owner provides his service), or if he first hires the owner and then borrows the cow, and the cow dies, he is not responsible. This is in the torah (Ex 22:14). But if he first borrows the cow and only after borrows or hires the owner, and the cow dies, he is liable, as it is written "the owner being not with [him], he shall surely make good" (22:13). So "with him" doesn't seem, according to the talmud, to just mean "with him when it happened", but also "with him in the hiring". There's a lot of discussion in the g'mara about when exactly the owner has to be present for it to count as being "with him". The g'mara concludes that, to avoid liability, you need to acquire the services of the owner no later than at the same time you acquire those of the cow -- even if it's in the same conversation, if you borrow the cow first and then engage the owner's services, it's too late. (There is also discussion of the different kinds of bailees, who have different levels of liability.) (94b-95)