Verse 2: And he opened the bottomless pit; and (Joel 2:2, 10) there arose a smoke out of the pit, as the smoke of a great furnace; and the sun and the air were darkened by reason of the smoke of the pit.
[He opened the well of the abyss] Which had been closed by the doctrine of the Prophets and Apostles (Pareus), and of pious Teachers and Councils (Gravius); but now was opened, with God permitting it, because men scorned the well of life and salvation, etc. (Pareus). [The sense:] He gave vent to the license of all evils (Gagnæus). The authority which he had arrogated to himself he now exercised, that he might bring in superstition and idolatry (Durham). He ushered in a seditious doctrine, that he is not to be subject to the Romans (Grotius).
[Arose the smoke of the pit (or, out of the pit [Beza, Piscator]) like the smoke of a great furnace] That is, Thick and dark. It signifies the great multitude of machinations of demons, most crafty and pernicious, arising from their burning fury, but about to disperse into smoke (Ribera). There is a continuation of the comparison already begun: for smoke deprives one of the view of the stars. In a manuscript it is καπνὸς καμίνου μεγάλης, the smoke of a great furnace, in which ὡς/as is understood. Κάμινος/furnace is wont to be set down in either the Masculine or Feminine gender. See Deuteronomy 4:20; Jeremiah 11:4; Matthew 13:42, 50 (Grotius). Others: Smoke is here understood of false and erroneous doctrine (Gravius, thus Piscator, Pareus, Cluverus, Gagnæus), which, after the likeness of smoke, hurts the eyes and obstructs vision, but in the end is dispersed (Cluverus). Just as a great amount of smoke clouds the vision, so also evil doctrines the mind (Grotius). This smoke is Mohammedism, which they themselves call Islamism (Mede’s Works 579). Others: The smoke here is the sooty Papal Theology, etc. (Pareus).
[And was darkened the sun and air, etc.] That is, the splendor of the Sun in the air, that is, heavenly doctrine in the Church (Piscator, similarly Durham): the air was darkened, with the rays of the Sun intercepted (Cluverus). The prior eclipse (under the fourth Trumpet [Forbes]) was pertaining to a third part; this one was total (Pareus, similarly Forbes). This means that this smoke obscured the power of intelligence and piety, and extinguished the prosperity of evil men. You will ask why I, who am wont to follow the proper signification of the words, take these things figuratively. Because it is apparent that the locusts are understood figuratively and Metaphorically (Ribera). The Sun here is Christ (Cluverus, thus Forbes, Pareus, Gravius), who is darkened, not in himself, but with respect to us (Cluverus), that He might not illuminate us, and foster spiritual life in us (Forbes); whom this star assailed (Cluverus), in relation to His person (Cluverus), office (Gravius), and merit, etc. (Cluverus). Air here is the faith and operation of the Holy Spirit, by which things, as from air, we have spiritual life (Gravius).
And he opened the bottomless pit; he was a means of hell’s breaking loose, by loosing Satan. And there arose a smoke out of the pit, as the smoke of a great furnace: I had rather interpret this generally of the great influence upon the world, that the devil, being loosed, had, in filling the world with ignorance, error, and wickedness, (for which this and the following age are infamous in all histories,) and then particularly of the errors this time abounded with. And the sun and the air were darkened by reason of the smoke of the pit; this influence of the devil darkened the sun of the gospel, and the whole church of that age, with ignorance, error, and abominable superstition in the worship of God, attended with the lewdness and debauchery of men in their lives, which usually go together.
 Greek: καὶ ἤνοιξε τὸ φρέαρ τῆς ἀβύσσου, καὶ ἀνέβη καπνὸς ἐκ τοῦ φρέατος ὡς καπνὸς καμίνου μεγάλης, καὶ ἐσκοτίσθη ὁ ἥλιος καὶ ὁ ἀὴρ ἐκ τοῦ καπνοῦ τοῦ φρέατος.  Κάμινος takes masculine endings, but the feminine article.  Deuteronomy 4:20a: “But the Lord hath taken you, and brought you forth out of the iron furnace (ἐκ τῆς καμίνου τῆς σιδηρᾶς, in the Septuagint), even out of Egypt…”  Jeremiah 11:4a: “Which I commanded your fathers in the day that I brought them forth out of the land of Egypt, from the iron furnace (ἐκ καμίνου τῆς σιδηρᾶς, in the Septuagint)…”  Matthew 13:42a: “And shall cast them into a furnace (εἰς τὴν κάμινον) of fire…”  Matthew 13:50a: “And shall cast them into the furnace (εἰς τὴν κάμινον) of fire…”