He was a sour young man and good of all his money and big place till he was married.
was sweet, pretty thing and he'd have walked the world over to get her a blade o' grass she wanted.
which theme from the novel is apparent in this passage?

The apparent theme of this passage might be:

-Patriarchal and toxic relationship.

It could be patriarchal because the woman is supposed only to be interested in money, marriage, and material things. Also, the man is portrayed as wealthy and powerful whereas, the woman is just a sweet and pretty unpowerful human being who needs the man's economic and psychological support. This imbalance of power and the stereotyping of the genders contribute to being a toxic relationship.

-1800s romantic relationships.

The stereotypes of men and women and the patriarchal system illustrated are typical issues of those times. It is also evident because these behaviors were socially accepted. Women being fragile, needing a house and money, and a husband to be happy are typical thoughts of those times which actually began to change in the 1900s.