(17) A smoking furnace.--The word really means the circular firepot which Orientals use in their houses to sit round for purposes of warmth. This one was wreathed in smoke, out of which shot "a burning lamp" (Heb., a torch of flame). For not two symbols, but only one, passed between the divided carcases. Abram had probably passed between them immediately after arranging them, and now Jehovah does the same. Fire is the recognised symbol of the Deity, as in the burning bush, the pillar of fire, the lightnings on Mount Sinai, &c.

Verse 17. - And it came to pass, that, when the sun went down, - literally, and it was (i.e. this took place), the sun went down; less accurately, ἐπεὶ δὲ ὁ ἤλιιος ἐγένετο πρὸς δυσμὰς (LXX.), which was the state of matters in Ver. 12. Here the sun, which was then setting, is described as having set - and it was dark, - literally, and darkness was, i.e. a darkness that might be felt, as in Ver. 12; certainly not φλὸξ ἐγένετο (LXX.), as if there were another flame besides the one specified in the description - behold a smoking furnace, - the תַּנּוּר, or Oriental furnace, had the form of a cylindrical fire-pot (cf. Gesenius, p. 869; Keil in loco) - and a burning lamp - a lamp of fire, or fiery torch, emerging from the smoking stove: an emblem of the Divine presence (cf. Exodus 19:18) - that passed between those pieces - in ratification of the covenant.

15:17-21 The smoking furnace and the burning lamp, probably represented the Israelites' severe trials and joyful deliverance, with their gracious supports in the mean time. It is probable that this furnace and lamp, which passed between the pieces, burned and consumed them, and so completed the sacrifice, and testified God's acceptance of it. So it intimates that God's covenants with man are made by sacrifice, Ps 50:5. And we may know that he accepts our sacrifices, if he kindles in our souls pious and devout affections. The bounds of the land granted are stated. Several nations, or tribes, are spoken of, that must be cast out to make room for the seed of Abram. In this chapter we perceive in Abram faith struggling against, and triumphing over, unbelief. Wonder not, believers, if you meet with seasons of darkness and distress. But it is not the will of God that you should be cast down: fear not; for all that he was to Abram he will be to you.And it came to pass, when the sun went down,.... It was going down when the deep sleep fell on Abram, and now it was quite gone or set:

and it was dark; which is not always the case as soon as the sun is set, there is a twilight for a while, and if a clear night the stars appear; but, as Aben Ezra observes, this was a dark and cloudy night; so it was a dark night, a time of great affliction and distress to the posterity of Abram, when their sun was set, or after the death of Joseph:

behold a smoking furnace; or the likeness of one, as Aben Ezra notes; for all this was represented in a visionary way to Abram, and was an emblem of the great troubles and afflictions of the children of Israel in Egypt, called the iron furnace, Deuteronomy 4:20, and may have respect to the furnaces in which they burnt the bricks they made, see Exodus 9:8; the Jewish paraphrases make this to be a representation of hell, which is prepared for the wicked in the world to come, as a furnace surrounded with sparks and flames of fire; and Jarchi says, it intimated to Abram, that the kingdoms would fall into hell:

and a burning lamp, that passed between those pieces; or a lamp of fire (o); an emblem of the Shechinah, or majesty of God, who afterwards appeared in a pillar of fire before the Israelites in the wilderness, after their deliverance out of Egypt, and when their salvation went forth as a lamp that burneth, of which this was a token: this burning lamp passed between the pieces of the heifer, goat, and ram, that Abram had divided in the midst, as was usually done when covenants were made, see Jeremiah 34:18; and here God made a covenant with Abram, as appears from Genesis 15:18; and, as a confirmation of it, passed between the pieces in a lamp of fire, showing that he was and would be the light and salvation of his people, Abram's seed, and an avenger of their enemies; only God passed between the pieces, not Abram, this covenant being as others God makes with men, only on one side; God, in covenanting with men, promises and gives something unto them, but men give nothing to him, but receive from him, as was the case between God and Abram: however, it is very probable, that this lamp of fire consumed the pieces, in like manner as fire from heaven used to fall upon and consume the sacrifices, in token of God's acceptance of them.

(o) "lampas ignis", V. L. Pagninus, Montanus; so Vatablus, Schmidt.