Why does the narrator note Marlow's resemblance to a Buddha, at the beginning as well as the end of Marlow's story?

It would seem that Marlow has to go through intense suffering before he achieves a sort of enlightenment at the end. Like the Buddha, Marlow looks to find meaning in life through experiences. The Buddha was also concerned with experiences that include multiple levels of consciences in one lifetime.Similarly, Marlow describes his journey at the beginning as happening "multiple lifetimes" ago.

I haven't read the book,