what is difference between ''the world of '' and ''a world of''?

Question

in this following sentence, what is difference between these phrases ''the world of'' and ''a world of''?

is it the same or what?

''An eternally surging sea of feelings, perceptions, volitions and states of consciousness: such is existence, such is Samsara, the world of arising and passing away, of growing and decaying, a world of sorrow, misery, lamentation and despair.''

Explain please...

source: https://books.google.com/books/about/Collected_Wheel_Publications_Volume_XXVI.html?id=Dgc4BgAAQBAJ#v=onepage&q=everywhere%20is%20found%20a%20perpetual%20change%20of%20material%20and%20mental%20phenomena.%20in%20this%20way%2C%20moment%20follows%20upon%20moment%2C%20day%20upon%20day%2C%20year%20upon%20year%2C%20life%20upon%20life.%20and%20so%20this%20ceaselessly%20changing%20process%20goes%20on%20for%20thousands%2C%20even%20aeons%20of%20years.%20an%20eternally%20surging%20sea%20of%20feelings%2C%20perceptions%2C%20volitions%20and%20states%20of%20consciousness%3A%20such%20is%20existence%2C%20such%20is%20samsara%2C%20the%20world%20of%20arising%20and%20passing%20away%2C%20of%20growing%20and%20decaying%2C%20a%20world%20of%20sorrow%2C%20misery%2C%20lamentation%20and%20despair.&f=false

Answer 1

the world of arising and passing away, or growing and decaying says that Samsara is, or means that.

a world of sorrow, misery, lamentation and despair does not say that that is what Samsara means, but is a comment or conclusion about it.

The difference is slight.