Parallelism (grammar)

Parallelism is a multi-part language structure that uses a sentence (or part of a sentence) that is very much like the one before it. The language parts often have the same grammatical structure and are said to be "in balance". The word "parallel" comes from a Greek word that means "next to one another."
In a parallelism, a first statement often will be repeated "in other words" by the second statement. These other words often add to the meaning of the first statement. For example, "The winter winds blow hard. The cold air pushes us back." In the second sentence, "cold air" is parallel to "winter winds", and "pushes us back" is parallel to "blow hard" (it is what the winter winds do). 
Parallelism is a common pattern in the writing of the ancient Near East and Biblical poetry. It can also be found in the work of European and American writers like William Shakespeare:"I'll give my jewels for a set of beads,"
"My gorgeous palace for a hermitage,"
"My gay apparel for an almsman's gown,"
"My figured goblets for a dish of wood,"
"My sceptre for a palmer's walking staff,"
"My subjects for a pair of carved saints"
"And my large kingdom for a little grave" 
(Richard II, Act 3, Scene 3, Lines 147-153)"" and Walt Whitman"There was never any more inception than there is now,"
"Nor any more youth or age than there is now,"
"And will never be any more perfection than there is now,"
"Nor any more heaven or hell than there is now."
("Song of Myself" Section 3, Stanza 2).