James wonders about the fallen angels that are currently bound in darkness:

As you know the angels bound in Tartarus were bound in eternal chains and eternal, blackest darkness: “For if God did not spare the angels who sinned but cast them down to hell [Tartarus] and delivered them into chains of darkness, to be reserved for judgment…” (2 Pet 2:4). But they were temporarily released in Revelation and appeared as scorpions (Rev 9:3-10).  But doesn’t this raise four problems?  

1. If they are in eternal darkness, how is this interrupted and their chains loosed when an angel from heaven opens the Abyss to release them for 5 months to torment mankind on the earth?

2. After the 5 months, are they then sent back to Tartarus?

3. They will eventually be thrown into the lake of fire.  But if the lake of fire does not have darkness, how are these fallen angels ceasing to be in the blackest darkness?

4. When the fallen angels in the Abyss are released, great billows of black smoke come out.  And where there is smoke, there is fire. So, wouldn’t these fallen angels be in the fire before they came out?

I don’t recall hearing a sermon on 2 Pet 2:4 or Rev 9:3-10. These incidents, past and future, are very rarely spoken of in Scripture or in most churches. I’ll tackle each question separately.

First, assuming that the “locusts” of Rev 9:3 refer to the fallen angels currently being bound, then they will be released from this eternal darkness for 5 months. I assume James’s concern is that the darkness is eternal. But there is no problem here. The fact that the darkness is eternal, and even that this is the eternal destiny of the fallen angels, does not mean that they cannot be released from it for a time.

Most commentators think that these beings called locusts are actually demons who have been in the Abyss/Tartarus. However, I believe that demons are not fallen angels (see here) and that demons are not currently in Tartarus (see Luke 8:31). Most likely these locusts are the fallen angels currently being held (2 Pet 2:4). (They could be special beings created at that time and released from Tartarus, but that seems unlikely.)

Second, if these locusts are the fallen angels that have been in bondage since Genesis 6, then it is most likely that they are immediately sent back to chains in Tartarus, though we are not told that.

Third, the lake of fire is indeed called “the blackness of darkness forever” in 2 Pet 2:17 and Jude 13. The unbelieving false teachers of 2 Peter 2 and Jude are men “for whom is reserved the blackness of darkness forever.”

James appears to be wondering how a fiery place can also be a dark place.

Imagine a volcanic eruption at night. There would be darkness that is pierced by the flames coming off of the lava. I think that is the idea with the lake of fire. I assume it will be a planet that has lava flows rather than oceans of water. Satan, the fallen angels, demons, and unbelieving humans will live on the land that is surrounded by fiery oceans. Evidently it will be a perpetual night there. (People who reject the light and choose the darkness get to live in it forever.)

Fourth, it is a common misconception, IMO, that those in Hades or Tartarus now are somehow on fire in the flames. No Scripture says that. I take it that the people in Hades and the fallen angels in Tartarus are in a fiery environment. They are not “in the fire.” They are in the fiery place. For more details, see my chapter on hell in The Ten Most Misunderstood Words in the Bible.

If I lived in the shadow of an active volcano, I’d be living in a fiery place. But I would not be floating in the fiery lava flow. (There are scientists who study volcanos and lava flows, and they have to live for a time in that very environment in order to collect data.)

I realize that I am speculating in several of my answers. But since Scripture does not give precise details about some of the things James asks, that is the best I can do.