| Quote #4
"Will anybody buy her?" said the man.
From the beginning of the auction scene, it's clear that Susan thinks of her husband as a "master" in an economic sense, as well as a legal and moral one – she refers to him, with possible irony, as her "present owner".
| Quote #5
Seizing the sailor's arm with her right hand, and mounting the little girl on her left, she went out of the tent, sobbing bitterly, and apparently without a thought that she was not strictly bound to go with the man who had paid for her. (1.80)
Susan's innocence is important: she doesn't realize that the "wife sale" that just took place isn't legally binding. After all, you couldn't just buy and sell people like slaves in 19th century England. But Susan doesn't understand this. If she did, her departure with the sailor would be like running away with someone to commit adultery. Since Susan thinks the marriage has been legally and morally transferred, she is innocent of any intentional wrongdoing.
| Quote #6
The sailor was now lost to them; and Susan's staunch, religious adherence to him as her husband, till her views had been disturbed by enlightenment, was demanded no more. (4.9)
We're never told that Susan loves the sailor, but she thinks it's her duty to stay with him "as her husband."