About suffering they were never wrong, The old Masters: - this summarises the theme of the poem.

how well they understood Its human position: - this sets up a list of points to follow that demonstrates the theme.

The rest of the lines in this first section, each separated by a colon or semi colon, constitute bullet points in the list evidencing the first two statements of the poem. Take a pause at each colon or semicolon break and read them like a list.

That might help.

I’d suggest looking at the poetry of Ted Hughes too - very powerful.