Parallelism is a characteristic feature of Hebrew poetry. Each structural unit is balanced by another with synonymous, complementary, or antithetical meaning. The units paired in this manner might be lines, stanzas, or even larger sections. For the purposes of our discussion, two parallel units will be called a pairing, and the two members of a pairing will be called branches.
A typical saying in Proverbs is a pairing of two lines. For example,
Treasures of wickedness profiteth nothing: but righteousness delivereth from death.
In more ambitious poetic structures, such as we find throughout the Psalms and the prophetic books of Isaiah and Daniel, the branches of a pairing might be separated from each other and fitted into a larger pattern. If a poem contains two pairings (the branches of the first designated A and A', the branches of the second designated B and B'), the pattern might be either ABA'B', known as step parallelism, or ABB'A', known as introversion, inversion (1), or chiasmus (2).
The same names are commonly used for larger assemblages of pairings, since these may also exhibit a stepwise or inverted ordering. If an assemblage contains two or more pairings, we will call it a group. Also, we will recognize two kinds of poetic structure as chiasmus:  a fully inverted group, or  a single pairing or inverted group enclosing a solitary branch; that is, any structure like ABA', ABCB'A', etc. A poem exhibiting the second kind of chiasmus is known as a palinstrophe (3).
As noted in the introduction to this commentary, the whole Book of Daniel has a framework of inverted parallelism. Our purpose here is to show that poetic design pervades the book at the level of individual chapters and passages.
Ernest Lucas finds chiastic structure in chapters 1, 3, 5, 6, and 7 (4). In chapter 1, for example, he uncovers the pattern ABCB'A'. Yet this is an oversimplification. The actual design retains parallelism down to small details. The true pattern is an elaboration of ABCDD'C'B'A'.
A. Nebuchadnezzar’s appearance on the scene (v. 1)
B. Seeming superiority of his Babylonian god to the God of Israel (v. 2)
C1. Outstanding qualifications of the Hebrew captives (vv. 3–4)
C2. Initiation of training to enter the king’s service (v. 5)
C3. Four captives named (vv. 6–7)
D1. Daniel’s approach to Ashpenaz (v. 8)
D2. Daniel’s enjoyment of exceptional favor (v. 9)
D1'. Ashpenaz’s response (v. 10)
D'1. Daniel’s approach to Melzar (vv. 11–13)
D'2. Melzar allows test to be carried out (vv. 14–15)
D'1'. Melzar’s response (v. 16)
C'1'. Outstanding qualifications of the Hebrew captives (v. 17)
C'2'. Entrance into the king’s service (v. 18)
C'3'. Four captives named (v. 19)
B'. Actual superiority of Jewish captives to the wise men (v. 20)
A'. Cyrus’s appearance on the scene (v. 21)
Again in chapter 3, Lucas misses the fine structure. He sees the pattern ABCDC'B'A' in verses 13–30. Yet Kenneth E. Bailey has shown that a much more intricate scheme governs the details of these verses.
The king in anger commands that the three be brought in.
Serve my God or you will be punished.
Who is the God who can deliver you?
The God we serve can deliver us from the king.
We will not serve or worship the golden image.
The fire is heated seven times.
The king orders the three bound and cast into the fire.
The three are bound and cast into the fire.
The king asks if three men were cast into the fire.
The king sees a fourth like a son of man.
The king orders the three to come out.
The three come out.
The fire did not touch them.
The God of the three delivered them from the king.
They did not serve or worship any God except God.
Speak against the God of the three and you will be punished.
There is no other God who can deliver in this way.
The king promotes the three in Babylon (5).
A central climax is framed on either side by five branches in opposite order. The climax itself is a single pairing of lines, and three of the pairings enfolding it are stepwise groups, each consisting of four lines with ABA'B' structure.
We will append to Bailey’s analysis the observation that verses 1–12 of the same chapter also have poetic structure. They show step parallelism in complex arrangement.
Background (v. 1)
A. Order to assemble (v. 2)
B. Compliance (v. 3)
A'. Cry of the herald (vv. 4–6)
1. Salutation to the assembled crowd (v. 4)
2. Command to worship the image (v. 5)
3. Punishment for noncompliance (v. 6)
B'. General compliance (v. 7)
Background (v. 8)
A''. Accusation brought by the Chaldeans (vv. 9–12)
1'. Salutation to Nebuchadnezzar (v. 9)
2'. Command restated (v. 10)
3'. Punishment restated (v. 11)
B''. Noncompliance charged against the three (v. 12)
Although Daniel’s book is everywhere shaped by the mind of a poet, the underlying design is never obtrusive. It varies from section to section, and it is always flexible enough to allow the occasional insertion of statements that do not quite fit, such as the background material added to the first twelve verses of Daniel 3. Nevertheless, once elucidated, the structure of each section is undeniable.
The impression given by Lucas is that parallelism is missing from the grand visions recorded in chapters 8 through 12. Yet in fact these are poetic compositions as well. The most notable example is the prophecy of the seventy weeks.
Gabriel’s message recorded in Daniel 9 has an ingeniously complicated design appropriate to its heavenly origin. It is ornamented with repetition of many thoughts and words, the effect being to create a giant stepwise group with the form ABCDEA'B'C'D'E'.
A. O Daniel, I am now come forth to give thee skill and understanding.
B. At the beginning of thy supplications the commandment came forth,
(A*. and I am come to shew thee; . . . : therefore understand the matter, . . . .)
C1. Seventy weeks are determined
C2. upon thy people
C3. and upon thy holy city,
D1. to finish the transgression,
D2. and to make an end of sins,
D3. and to make reconciliation for iniquity,
E1. and to bring in everlasting righteousness,
E2. and to seal up the vision and prophecy,
E3. and to anoint the most Holy.
A'. Know therefore and understand,
B'. that from the going forth of the commandment
C'3'. to restore and to build Jerusalem
C'2'. unto the Messiah the Prince
C'1'. shall be seven weeks, and threescore and two weeks:
D'4. the street shall be built again, and the wall, even in troublous times.
D'5. And after threescore and two weeks shall Messiah be cut off, but not for himself:
D'6a. And the city and the sanctuary shall destroy the people of a prince coming. And its end shall be with the flood,
D'6b. and until the end shall be war; determined are desolations.
E'4'. And he shall confirm the covenant with many for one week:
E'5'. and in the midst of the week he shall cause the sacrifice and the oblation to cease,
E'6'a'. and upon a wing as abominations a desolator, even until the end.
E'6'b'. And that which was decreed shall pour out on the desolator.
We have used underlining to show some of the repeated concepts. The italicized portion is taken from Jay P. Green’s interlinear translation (6). Others who have recognized Gabriel’s message as Hebrew poetry include William H. Shea, who offered a fascinating analysis of the structure made evident by stress patterns (7).
Branches A and A' contain direct exhortation to Daniel. B and B' refer to commandments from an unnamed source. C and C' lay out the exact time until the fulfillment of a divine promise. D and D' speak of events preceding, attending, or soon following the first advent of Christ, E and E' of events near His second advent.
So far we have examined only the two main series of steps. But poetic craftsmanship has not neglected the details. After B comes a parenthetical line parallel to A. As a result, the introduction to the message is a complete symmetrical composition set apart from what follows. The ABA' configuration at the beginning of the message is balanced at the end by the same configuration within both D' and E'.
C and C' are an inverted group with three complementary pairings. Branches 1 and 1' specify a term of weeks. Branch 2' speaks of the King, whereas branch 2 speaks of the people He will govern. Branches 3 and 3' are alike in their reference to Jerusalem.
D and E are a stepwise group with three complementary pairings also. The first branch in each case speaks of sin being defeated and the second of holiness being established.
The structure of D' and E' is rather more complex. In D'4 the city rises, in D'5 the Messiah is rejected, and in D'6 the city falls. In E'4' the Antichrist rises, in E'5' God is rejected, and in E'6' the Antichrist falls. Thus, the two sequences form another stepwise group with three complementary pairings, the steps expressing the concepts of rising, being rejected, and falling. Yet D' within itself is a palinstrophe with antithetical outer branches. So too is E'.
The final steps, D'6 and E'6', are expanded so that together they also form a stepwise group, but with only two pairings. The first, D'6a and E'6a', is complementary, since both branches envision future moments when evil seems to emerge victorious. But the second, D'6b and E'6b', is antithetical. D'6b is another sad prophecy, foretelling that the Romans would nearly succeed in exterminating God’s chosen people, whereas E'6b' gives us reason to rejoice, for it promises overthrow of the Antichrist. Gabriel’s message therefore closes on a triumphant note, assuring us that "at last the morning glorious will rise, when evil, raging to prevail, is crushed by warriors from the skies."