Which stylistic devices are used in these lines?

Metonymy

Personification

Simile

Paradox

Before we can decide which of the above literary devices Milton used in his poem, On His Being Arrived to the Age of Twenty-Three (1631), we must first understand all of our options.

First, let's consider metonymy. Metonymy means to substitute one word for another which has attributes associated with the overall idea being conveyed. For example, when we say, "He was fishing for information," the word "fishing" represents stealth and the idea of someone slyly collecting information by luring out what they want to know. Other examples of metonymy are, "She really hogged the microphone!" and, "The pen is mightier than the sword."

The second option, personification, is a technique whereby an author turns a thing or an idea into a person by giving it human qualities or personality traits. Things in nature are oftentimes personified in poetry and prose. Some good examples of personification are, "The sun smiled upon the fields," and "The angry ocean swallowed the ship whole."