<span>Being a teacher means having many benefits: personal job fulfillment, a strong union, supportive friends and colleagues, and many holidays and breaks off during the school year.</span>
The pattern of end rhymes I presume.
This quote has no mention of a deity (divine authority) or society as a whole (civil obedience), and the only mention of gender is the author's reference to his sibling as "brother." The final line "<span>I won't be caught betraying him." drives the assumption that failing to do his "duty to [his] brother" would violate some sort of bond between he and his brother. Since we only know this relationship as familial, we must assume familial loyalty is the theme.</span>