At the 1858 Illinois Republican State Convention, Abraham Lincoln pronounced, "A house divided against itself cannot stand".

(you didn't attach a copy of the poem, but i'm answering as best as i can)

since a simile compares two unlike things using like or as, it kind of gives an item the ability to do something it can't.

example: "the player was like a tiger on the field"

in this sentence, the simile conveys the idea that the player was fast and strong, like a tiger.

we would need to be able to read the passage in question to determine which factor allowed david believe he could defeat goliath. post the passage, and i'd love to out.