The blue ringed octopus is hard to see due to its size (about a pencil).
When Gerasim says: " It's God's will. We shall all come to it some day", He expresses that he is a believer. This is pretty much related to his spirituality.
I think it's the 3rd one. Might be wrong though.
The stranger's interaction with Elisa at her garden is different from Henry's interaction with her at her garden. The stranger's interaction with Elisa was a bit awkward since they were not introduced formally and Elisa was a bit professional as she entertains the stranger. On the other hand, Elisa was comfortable with Henry since they have been friends for a while already.