Quote 1
"You see the mounds? I come here and prayed, nows and thens, when I thought maybe a Sunday would be about doo. It weren't quite a chapel, but it seemed more solemn like; and then, says you, Ben Gunn was short-handed--no chapling, nor so much as a Bible and a flag, you says."
So he kept talking as I ran, neither expecting nor receiving any answer. (15.54-5)
As Ben Gunn and Jim travel across the island, Gunn keeps narrating as though he is alone and doesn't expect a response from his audience. He is clearly used to talking to himself, which reminds us that he has been alone for three years. Stevenson is amazingly skilled at using language to suggest character. Here, we definitely get the sense that Ben Gunn has gotten a little weird during his years of solitude.
Quote 2
"Come aboard, Mr. Hands," I said ironically.
He rolled his eyes round heavily, but he was too far gone to express surprise. All he could do was to utter one word, "Brandy." (25.11-2)
Like Billy Bones, Israel Hands is physically badly off (from a stab wound rather than a stroke) but he still wants nothing more than alcohol. The dependence on alcohol leaves all of these characters in a sorry state not only because they're drunk all the time, and therefore careless, but also because when they're sick or injured, they become totally dependent on whoever is nearest to them. In both Billy Bones and Israel Hands's cases, that would be Jim.