Two English poems that use many allusions are John Milton's "Paradise Lost" and T.S. Eliot's "The Waste Land." For instance, the first line of "Paradise Lost" mentions "man's first disobedience," an allusion to Adam's disobedience to God in the book of Genesis. Allusion is a very common literary device by which a writer intentionally but indirectly references another work, especially one of religious, mythological or literary significance.
One of the most allusive poems of all time, Milton's "Paradise Lost" alludes to the Bible, Virgil's "Aeneid," Homer's "Odyssey," and Ludovico Ariosto's "Orlando Furioso" all within the first 20 lines. To readers who are familiar with these texts, allusions serve as a shorthand way of referencing shared knowledge without requiring detailed explanations. Allusions also place the alluded text in a new context, where it acquires new meanings.
A poet may also allude to sources that are not strictly literary. For instance, T.S. Eliot's poem "The Waste Land" contains the line "London Bridge is falling down falling down falling down," an allusion to a common nursery rhyme. This allusion is also a good example of the way an alluded text takes on new meaning in context, since the line that appears light-hearted in the nursery rhyme acquires a more serious tone in Eliot's poem.