What suggestion does Hawthorne make with the rosebush in The Scarlet Letter?

Hawthorne employed many literary elements into The Scarlet Letter. On almost every page you can find one. Two common examples are:

"He now dug into the poor clergyman's heart, like a miner searching for gold; or, rather, like a sexton delving into a grave, possibly in quest of a jewel that had been buried on the dead man's bosom, but likely to find nothing save mortality and corruption" (Hawthorne 117). - Simile

"We have as yet hardly spoken of the infant; that little creature, whose innocent life had sprung, by the inscrutable decree of Providence, a lovely and immortal flower, out of the rank luxuriance of a guilty passion" (Hawthorne 81). - Metaphor