Daniel chs. 10-12 are considered a literary unit by most commentators and Daniel chapter 10 is usually regarded as introductory. There are numerous curiosities in this chapter which remain unanswered by most commentaries. Firstly, although it is set during the reign of Cyrus no mention is made of any edict allowing the Jews to return to their land. Secondly, the vision is received after a period of fasting but this occurred during the month of Passover leading Collins to remark, “Daniel apparently fasted through Passover, but the author does not appear to notice this implication of the dating”. Lastly, why does this chapter contain a “behind the scenes” glimpse of angelic activity as an explanation for the three week delay (the period of Daniel’s fast) between the sending out of the angel and his coming to Daniel with the revelation?
Daniel’s career lasted until the first year of King Cyrus (Dan. 1:21) and this seems to contradict the reception of a revelation in the ‘third year’ of Cyrus (Dan. 10:1). Leaving aside the fact that the OG renders this as ‘first year’ (which is possibly a harmonisation with Dan. 1:21) there is no reason why Daniel could not have received a revelation after his official career had ended. The ‘third year’ of Cyrus (536BC) is seventy years after the “third year of the reign of Jehoiakim” (Dan. 1:1) and this obviously raised the expectation that the seventy year captivity had ended and would result in complete restoration including the rebuilding of the temple. This did not occur and Cyrus’ edict proved such a disappointment that it is not even mentioned in Daniel. Interestingly, Cyrus is styled ‘King of Persia’ which many commentators regard as a late description from the Hellenistic era, Continued ˃
 Hermeneia, 373
 So Towner, “Cyrus is never actually called “King of Persia” in the ancient records after his conquest of Babylon in 539 B.C…..so we must conclude, as we have so often done before, that the chronological framework provided for the Book of Daniel has only a loose connection to the actual course of history and shows precisely the kind of imprecise command of details that we might expect from a writer who lived more than three hundred and fifty years after the dates being used”. W. Silbey Towner, Daniel,(John Knox Press: Louisville,1933 reprint 1984),149
however, both the Chronicler and Ezra employ the same title (2 Chron. 36:22; Ezra 1:1) and the emphasis on ‘Persia’ is obviously meant to contrast with ‘Mede’ in the title ‘Darius the Mede’ of Dan. 11:1. This presents great difficulties for interpreters who need to explain a conquest of Babylon by ‘Darius the Mede’ at the same time that Cyrus was conquering Babylon. Usually this is resolved by regarding ‘Darius the Mede’ as an appellative for Cyrus or as a subordinate empowered to act on his behalf.
These explanations are unsatisfactory and the solution is to be sought in the fact that conquest of Babylon by Cyrus did not live up to expectations. Instead the conquest of Babylon by Darius Hystaspis (our Darius the Mede) which occurred sixty two years after Nebuchadnezzar’s last deportation, did live up to expectations, for it saw the rebuilding of the temple seventy years after it had been destroyed. This was seen as a legitimate fulfilment of Jeremiah’s seventy year prophecy and his prediction that the Medes would overthrow Babylon. It is for this reason that Darius Hystaspis (who had both Persian and Median ancestry) is styled ‘Darius the Mede’ to differentiate him from Cyrus ‘King of Persia’. The 21 day delay between the commencement of Daniel’s fast and the reception of the revelation represents the 21 year delay in the fulfilment of the prophecy, which did not occur under Cyrus but 21 years later under Darius.
The 21 year delay in the Exodus from Babylonian captivity is emphasised by the unusual feature of fasting during Passover.  The Continued ˃
 The Nabonidus Chronicle 2:15 (ANET,306) uses the same title
 Daniel is in “mourning” which is a synonym for fasting (cf. Matt. 9:14-15) and is described in v.12 as “humbling oneself”
fast is highly inappropriate for a feast that is meant to commemorate deliverance and more fitting for the Day of Atonement. The inconsistency is deliberate and Montgomery has noted that Daniel’s statement that he “ate no pleasant bread” (v.3), finds a parallel in the “bread of affliction.” At the Passover the Israelites were bidden to eat unleavened bread the “bread of affliction” (Deut. 16:3). The Passover commemorated deliverance from the bitter servitude of Egypt – by comparison the Babylonian exile was mild, however the realization that sinfulness had separated the nation from their God and that the restoration under Cyrus had not materialised, left Daniel unable to celebrate Passover in the usual manner. This explains the “death-resurrection” sequence that is found in vv.9-11, particularly; “…I was in a deep sleep on my face” which is reminiscent of the “deep sleep that fell upon Abram” in Gen. 15:12. Significantly this also occurred on the Passover in the context of the unconditional covenant concerning the land (v.7) and the prediction (vv.13-14) that his descendants would suffer in a “strange land” (Egypt). On that occasion the ‘death’ of Abram signified that the promise would be fulfilled after Abram’s death and that personal enjoyment of the covenant could only occur after the resurrection. This puts to rest the charge that resurrection is a late (post-exilic) development that is first introduced in the book of Daniel, as the idea of resurrection is implicit in the Genesis covenant. Daniel understands the implications of resurrection in the Continued ˃
 James A. Montgomery, A critical and Exegetical Commentary on the Book of Daniel, (ICC; Edinburgh: Clark,1927),406
 This anticipates the persecutions of Antiochus who “turned into mourning” the feasts of Israel as he made it impossible to observe them properly (1 Macc. 1:39, 45).
 Exodus 12:41 makes it clear that deliverance occurred four hundred and thirty years later on the selfsame day marking the revelation to Abram as the Passover day (night). In Gal 3:17 Paul has the interval between the covenant and the law as 430 years and in Seder’ Olam the 430 years are reckoned from the covenant of Genesis 15 to the Exodus. Therefore the 400 years of Gen. 15:13 references the period of affliction not the total interval between promise and fulfilment.
context of the covenant relationship and the theme is carefully developed, first with the story of Daniel in the lion’s den, then with his reaction to the revelation and finally it is made explicit at the end of the book.
Goldingay (1989:285) observes that Dan. 10-12 is “situational midrash rather than expository midrash. Its starting point is more the problems raised by present experience, which the interpreter seeks to address by means of Scripture, than problems raised by the text in its own right”. It is certainly true that the influence of Isaiah is encountered in a chapter that has midrashic elements on Isaiah 40-41 as the following table makes clear:
This challenges interpreters to ask why the revelation in Dan. 10 is framed around Isa. 40-41, particularly, why the first mention of the Continued ˃
archangel Michael in the O.T. occurs in the book of Daniel (10:13, 21; 12:1). The name of the archangel Michael poses the question; “Who is like God?” significantly, the same rhetorical question is asked in the Song of the Sea that celebrates the Exodus from Egypt;
“Who is like You, O LORD, among the gods? Who is like You, glorious in holiness, Fearful in praises, doing wonders?” (Ex. 15:11)
Isa. 40-41 is shot through with allusions and echoes that recount the Passover Exodus from Egypt  and this reinforces the importance of the text to the Passover setting of Daniel 10. Deutero-Isaiah (chapters 40-55) is usually attributed to a post-exilic author but along with A. Perry and H.A. Whittaker we follow an eighth century reading; “Our counter claim is that the echoes illustrate how Isaiah’s rhetoric is directed against the Babylonian envoys and Merodach-Baladan. Isaiah’s argument is that Yahweh is the one true God and the one who has chosen his Servant (Hezekiah). Since ―the Servant of ―the deity is a common motif for the Near Eastern king, Isaiah’s argument requires a pre-exilic context of interpretation.” 
This places the context of Isaiah 40-41 during the reign of Hezekiah, when the Assyrian King Sennacherib insolently challenged the God of Continued ˃
 Fear not…be not dismayed (Isa. 41:10) was spoken to Israel at the Red Sea (Ex.14:13), and when they stood on the borders of the Land of Promise. “I am with you” (41:10) alludes to the assurance given to Moses (Ex. 4:12) “I will uphold you with My righteous right hand.” (41:10) echoes Moses having his arms supported in the battle against Amalek (Ex. 17:12) and, “they that contend with you” (Isa. 41:12) will perish (Pharaoh’s army Ex. 14:3); the promise of water (Isa. 41:17, 18) alludes to the smitten rock in the wilderness (Ex. 17:6).
Israel (See Isaiah ch.14; 2 Kings 18:22,30,32-35; 19:4,10-13,16-19,22-24,27,28,34,37). All the nations before him are as nothing….less than nothing and vanity (Isa. 40:17). God has not forgotten, neither is he deaf nor is he tired (Isa. 40:28). Significantly, the deliverance of Jerusalem from the hand of Assyria occurred at Passover. Commenting on Isa.41:25 H. A. Whittaker  (who reads “call on my name” as “called by my name”) observes: “The most likely explanation is that this recalls the work of the angel of the Lord. Michael, the great prince who stands up for the children of God’s people, was at work for Jehovah: “I have raised up (the Assyrian) from the north (Isa. 10:28-32), and he is come; from the rising of the sun he is called by my Name (mi-cha-El; cp. Ex.23:20, 21). “This was the work of the angel of the Lord before it came to pass (Isa. 8:7; 10:6, 7). Sennacherib was “a ravenous bird from the east” (Isa 46:11). But the rebuking of the invaders pride was also assigned to the same angel: “He shall come upon princes (Assyrian s’ganim) as upon mortar, and as the potter treadeth the clay.” This was also declared beforehand and was duly fulfilled: “The angel of the Lord went forth, and smote in the camp of the Assyrians” (Isa. 37:36).
Daniel 10 alludes to, or echoes texts that have the Exodus and Passover deliverance as basis – the covenant made with Abraham on the Passover, the Passover deliverance of Israel from Egypt and the salvation of Judea during the reign of Hezekiah, which also occurred at Continued ˃
 H. A. Whittaker, Isaiah, (Biblia, 1988 reprint 2000), 52-53. See also P. Wyns, The Passover deliverance in 701 in the Christadelphian eJournal of Biblical interpretation (eds. A. Perry, P. Wyns, T.Gaston, J.Adey, D. Burke, 2011,vol.5no.1, 2011), 50-61 [cited Jan 2011] @ Access here
 Isaiah 41:25 - “I have raised up one from the north, And he shall come; From the rising of the sun he shall call on My name; And he shall come against princes as though mortar, As the potter treads clay”.
Passover. However, Daniel fasts 21 days through the feast because the promised deliverance under Cyrus did not materialise, instead it occurred 21 years later under Darius Hystaspis (Darius the Mede). The revelation vouchedsafe to Daniel is by way of reassurance and offers him a glimpse into the machinations of the angels of the nations and the cosmic resistance that caused the 21 year delay. Nevertheless, Yahweh does not weary in upholding his covenant love – Jeremiah’s ‘seventy’ prophecy was fulfilled after all, only not in the way that the exiles expected. Therefore the 21 year postponement in the reign of Cyrus functions as an introduction to a much, much, longer delay and further desolations in the Greek era. Even so, it would be many years after the death of Daniel (and Abraham) before the Passover deliverance wrought by the Messiah (which accorded a foretaste of the resurrection in the first century) and even longer still (more than 2,000 years) before the faithful awake to everlasting life (Dan.12:2) and the full realization of the unconditional covenant made with Abraham on that distant Passover.