What can you say to someone whose loved one (e.g. spouse or parent) is dying?
Assume if you can that in the West, e.g. Europe and America, although people (strangers) might have heard the first thing about Buddhism, but they haven't formally practised it nor intentionally studied its doctrines in any detail (what if they've just seen some "fake Buddha quotes" for example). So, although a simple catchphrase (perhaps just a few words of Dhamma) might help a Buddhist as a "reminder", someone else (a non-Buddhist) might not recognise/understand that.
Or I would ask, what you could you even say to a layperson who does know some Buddhism -- except that most of the people who I'm likely to contact don't, and I doubt it's a moment to begin to lecture them (uninvited). For example a simple statement like, "Don't be attached", might sound like, "Don't be ill" -- or, "abandon that person" -- which might seem impractical, too academic, or even cruel if you don't understand the context (and might need more explanation than is possible in the context). Or for example, saying, "Buddhist doctrine says that..." sounds like they're being lectured, and at a moment when they're concerned about something other than Buddhism (so maybe that too is not the right way to frame or to open a conversion).
I don't want to talk too much about what I think the difficulties are, so I'll try to stop; if you have questions (about this question), you can a comment to ask.
But as well as being reluctant to lecture someone unasked, I'm generally not sure what to say if someone tells me that they're suffering somehow. For example if someone is mentally ill and tells you something about (or something based on) their delusions or hallucinations, I think I've read that maybe people shouldn't encourage (nor perpetuate nor even argue against) those fantasies (e.g. "yes" and "tell me more about that" or "that's untrue"), and instead you're supposed to talk about consensual (maybe conventional) realities. So I worry that "tell me about your suffering" (or even "yes that's sad" or "I'm so sorry") might only reinforce the suffering, especially if I've nothing to add, nor even understand how to steer their thinking (steer the topic) by asking questions -- possibly (at the risk of being prejudiced) it might be good for them to experience "brahmaviharas", or "recollection of virtue", or even just some "calm" etc., but I'm not sure how someone might get there by my asking them questions -- so maybe that (asking questions) is not the right approach either, or is it?
I quote this answer as an ideal -- slightly out of context, because that was posted as an antithesis of "fear" or aversion -- but perhaps this is an example of an ideal:
... basically leave all Dharma-Theory home and dive into the world, while learning to be authentic and helpful. The end result of this is an image of someone very warm, strong, and open, who has enough inner power and confidence that he or she can be very down-to-earth, very real, without formalities and artificial boundaries that come from fear. This is very different from the aloof ascetic image cultivated on the previous stage. It is someone very warm and very real.
The absence of overt Dharma-Theory (in relating to others) might be appropriate (though perhaps you're informed by theory, or practice, even if you're not teaching it formally/explicitly).
I guess I'm looking for answers from personal experience (your own or someone else's) -- what kind of thing can you say that actually works in the circumstance, is helpful?
When I've tried to do this in the past, it was by trying to share (recollect, recount) what might have been helpful in retrospect from my own experience (of a relationship with a dying loved one). My doing that might depend on making assumptions about the people I'm talking to, so, and I've only limited experience -- perhaps you can tell me more experience or even generalise from experience ... or not?
It happens and will happen a lot (that I meet people in this situation), it would be good to be better prepared for that if possible.
At the risk of being off-topic (maybe delete it if it is), here's a story -- as an example of what seems to be a beneficial effect of a kind word (i.e. it "kept me unexpectedly calm").
Someone posted a question on Twitter -- What is the kindest thing a stranger has done or said to you? -- which has thousands of replies.
And one of the answers to that question, which I thought was remarkable, was this one (quoted here):
One of my twins was born with multiple heart and esophageal defects. Had open-heart surgery at 47 hours old, weighing only 4.5 lbs. When the surgeon described the procedure, it sounded impossible. But the surgery went well. He has more to go, but we let our guard down.
24 hours later, get a call that he's failing (he was at one hospital, my wife and his twin at the other, and I'm running back and forth). It looks grim; Plan A is an untested long-shot, and there's no Plan B. I race out of Hospital 1 to grab a cab to Hospital 2.
Get in cab, driver asks me how I want to get there. Exhausted and angry, I snarl "my son is dying at Hospital 2, so whatever way you think is faster."
We drive in silence for a very long time.
As we get near, he starts to ask me what is wrong, and I tell him. He replies, as we pull into the hospital, "I am Muslim, and tomorrow is Friday. I will pray for him all five times tomorrow." And as I hop out of the cab, I hear him start to pray, "bismallah ar-rahman...."
As I raced thru the hospital, that one small act of kindness, after I had been so surly to him at the start, stuck with me, and for some reason kept me unexpectedly calm during a night of staring at the Plan A machine, hoping it would defy expectations and work.
It wasn't some huge thing. But that small act of compassion made such a huge difference as I spent the night alone w this insanely strong but insanely sick little boy--and who is now quite healthy.
It's one of the few things that still chokes me up when I think abt those days.
I suppose the bits of Islamic doctrine which a non-Muslim might know are "Inshallah" (something to do with awareness that things happen according to God's will i.e. not always our will) -- and "bismallah ar-rahman" (which the OP quoted and remembered) i.e., "In the name of God, the Most Gracious, the Most Merciful" -- maybe any outcome is "a mercy".
Please don't answer that that's not Buddhist doctrine, that isn't what I'm asking -- I quote this as an example, because I'm impressed with the effect[s] it had on the person to whom it was said.
My question might be, what could a Buddhist (instead of a Muslim) possibly say in that situation? It might be difficult if the person you're talking to knows even less about Buddhism than about Islam -- so they might not "recognise" what you say. But Dhamma is "evident", isn't it, so maybe there's always some common ground already, whether they've ever studied Buddhism or not.
What might you say that could help a stranger? Or help a friend who you're not going to see again, maybe someone who lives far away? What if it's just a short conversation, in person -- or, what if you're writing a personal letter to distant family or an old friend in another country (or maybe a phonecall would be better)?
One other thing I see in the story above is that a person who is suffering will make things worse -- "Exhausted and angry, I snarl" and "after I had been so surly to him". So it might be important to help, it affects everyone, even including those they're trying to care for; but it can also be difficult, a time when they might be more troubled, less tolerant and less outgoing or communicative themselves -- i.e. more "surly" (or if not surly, more guarded).