In Thomas Gray's "Elegy Written in a Country Churchyard," poverty is said to have stopped the villagers from achieving the kind of "greatness" achieved by, say, Cromwell or senators. Gray writes:
But Knowledge to their eyes her ample page
Rich with the spoils of time did ne'er unroll:
Chill Penury repressed their noble rage,
And froze the genial current of the soul. (49-52)
One might say that lack of knowledge and poverty prevented them, but due to the use of the colon, I interpret these lines to mean that knowledge did not unroll because of their poverty. Others may disagree.
Concerning lines 85-92, these lines deal with the human need to be remembered after death. One can go back as far as the Greek epics to demonstrate how central this is to the human mind. A poem fulfills this need, if it's exceptional and a little lucky, anyway, by immortalizing its subject.
In this case, the churchyard and the villagers buried in it are immortalized by Gray's poem.