Okay thank you got it

Okay, is it like this? In the Zether paper, they have given we can lock our accounts to a smart contract. This means that the smart contract can be made to interact with specific eoas and contracts. (not the other way round, i.e., we (eoa account) can interact with only specific contracts, cannot send/receive funds to/from others except this contract ??

Okay, is it like this?

May I please know the answer for my updated (modified) question?

Okay, I got this. But, I have edited my question - with reference to a paper from where i got this doubt.