Life insurance is very simple.

You work hard all your life, and give a certain proportion of the fruits of your labour (say, five minutes sweat and toil per day) to a strange man who tells you that you'll feel so much better having paid up.

His justification for these payments is as follows: much as you can plan your future, you could some day end up unexpectedly dead. This tends to be a rather nasty surprise, and so at this point the strange man will give you back all the money you gave him, or indeed, even more in an attempt to cheer you up.

All of which is terribly nice, but not entirely useful given you are of course still dead - and to date, the discussion about legal tender in the afterlife is still at a tentative stage.