What's a good Mexican poem without some biblical imagery? Mexican culture is steeped in Catholic tradition, and, often, so is its poems. This one is no exception. All of the rebellion of poetry is against holy things and involves desecration and other profane acts. There are also some images that come straight out of Bible stories, so the echoes ringing in its readers' heads will be clearly religious.
Line 3: The rules that poetry breaks aren't in the civil code, they're holy commandments, which is a pretty dangerous thing to break, if you believe in hellfire and damnation.
Line 6: Any time you hear somebody talking about forty days and forty nights, you can bet you're dealing with a biblical reference. In the Bible, this period of time is often used for trials and tribulations, like surviving a worldwide flood or going out in the desert to eat bugs. Ew.
Line 7: Poetry turns worship around and, instead of pointing it at something holy like a god, it points it at the self, the poet! That's pretty blasphemous, but then it is also the desecration of the self, which means making the self profane, or bringing it down to earth.