Oswalt’s commentary on Isaiah is masterful. Furthermore, not only is Oswalt helpful in elucidating the text, he is also unafraid to challenge unbelieving scholarship.
On Isaiah 36:20
It is hard to understand how those who can assert that the theological function of this passage is to claim that God acts in history can then assert with equal force that God did not act in this event (cf. Clements). If they do so to demonstrate that biblical theology is self-discredited, that is one thing. But to speak of the worth of the theology while denying its evidence is very odd indeed. [1:638, n. 21]
On Isaiah 42:20
The change from second person to third in the middle of the verse has been troublesome to translators since the time of the LXX . . . But none of these stratagems seems necessary given the well-documented tendencies for this kind of shift in Hebrew writing. [2:131-32]
On Isaiah 45:18ff.
These verses show a rather profound understanding of paganism. Because paganism refuses to admit of a God who stands outside the cosmos, it must posit that the beginning of all things was matter in chaos. Out of this chaos the gods emerged. The ordering of the chaos was something of an afterthought on the part of the gods to protect themselves from the ever-present danger of its reemergence. Humans are even more of an afterthought, created primarily to take care of the gods. Since the gods have no commitment to and accept no responsibility for humans, they have no interest in communicating with them. If humans wish to divine the future, they must resort to mediums, wizards, and necromancers (cf. 8:19). To all of this Isaiah says a resounding no! Chaos did not exist before God, and God did not bring a meaningless chaos into existence. Rather, the preexistent God created the cosmos specifically for human habitation. [2:218]
On Isaiah 49:6
Some modern translations (e.g., NRSV [ESV, NASB]) render the final phrase of the verse as ‘that my salvation may reach to the end of the earth.’ While this is not impossible, it is not the obvious sense of the grammar. The plain sense is: ‘I appointed you . . . to be my salvation to the ends of the earth.’ The former translation obscures the point that the Servant is not merely to be the means of God’s salvation coming to the world, he is to be that salvation. All the versions confirm this understanding.” [2:294]