EXODUS
3:2-8, excerpts
The Mal’ak-YHWH appeared as a flaming fire (לַבַּת־אֵשׁ) in a bush.
God called to him from the midst of the bush: "I am the God of your father, the God of Abraham, the God of Isaac, and the God of Jacob. Then Moses hid his face, because he was afraid to look at God.
YHWH said, "I have come down (וָאֵרֵד)" to save the sons of Israel from the Egyptians.
The fire does not hide YHWH; the fire is YHWH. This is corroborated in both this passage (where both Moses and God say that "YHWH appeared to you," כִי־נִרְאָה אֵלֶ֫יךָ), and elsewhere in Torah (where this phenomenon is called "The Fire of YHWH, אֵשׁ־יהוה)." Sinai shows the same manifestation, but His manifestation is given a new name.
→ See Fire
13:21
Yahweh went before them [the Exodus travelers], leading the way, in a pillar of cloud by day, and by night in a pillar of fire for light.
The pillar is equated with The Mal'ak-YHWH in Exodus 14:19: "The Mal’ak Elohim was going before the camp of Israel, and when The Mal’ak Elohim moved behind the Israelites, the pillar of cloud moved behind them too." In this theophany, the cloud and fire appear to be acting as a screen for the form of God [not The Father], and this will be the case in much of the rest of Exodus.
16:10b
The Kabod YHWH appeared within the cloud.
The Kabod YHWH is a new manifestation of God as an unearthly light or fire, almost always veiled by a cloud. Here He appears to the entire assembly of the Exodus travelers (sons of Israel and the mixed multitude of Egypt). The voice of YHWH comes out from the cloud as well, similar to the fire-voice dual theophany at the Burning Bush.
→ See the academic paper The Kabod YHWH for a fuller treatment of this theophany.
24:9-17, excerpts
Moses and Aaron, Nadab and Abihu, and seventy elders of Israel went up—and they saw the God of Israel. Under His feet there was something like a pavement made of sapphire, clear like the sky itself. But He did not lay a hand on the leaders of the sons of Israel. So they saw God, and they ate and they drank.
The Kabod YHWH dwelled on Mount Sinai, and the cloud covered it [the mountain] for six days. On the seventh day He called to Moses from within the cloud. Now the appearance of The Kabod YHWH was like a devouring fire on the top of the mountain to the eyes of the people.
The Kabod is explicitly described as fire this time, and a select group (of 74 people) are allowed to go up onto Mount Sinai and see what lies behind the veil. They see a human figure, with feet(!), and He is called "God." Sinai is one of at least two episodes in Exodus where a figure can be seen within a veiling cloud or fire, looking something like The Mal'ak YHWH.
34:5-6, 8-9a
So YHWH descended in the cloud, and stood with [Moses] there. And [YHWH] proclaimed The Name of YHWH. Then YHWH [The Kabod] passed by before [Moses's] face, and YHWH [the one beside Moses] proclaimed: "YHWH, merciful and gracious God, longsuffering, great in covenant loyalty and truth [...]." With haste, Moses bowed his head to the earth and worshiped. Then [Moses] said, "If I have found favor in your eyes, Adonai, allow Adonai to go into our midst."
This is one of the most misunderstood passages I have ever exegeted. Moses was not the one proclaiming The Name of YHWH in 34:6. In 33:19, YHWH was the one who said "I will proclaim The Name of YHWH before you" (וְקָרָאתִי בְשֵׁם יהוה לְפָנֶ֫יךָ). YHWH is the one speaking in 34:6. The Kabod YHWH was the one to pass before Moses [33:22]. YHWH thus praises The Kabod YHWH and calls Him "YHWH." We have two-who-are-the-one-YHWH; now as the passage ends we see two-who-are-the-one-Adonai (a special name for God, literally "my Lord").
→ See Theophany in Torah for a broader look at God showing up in Exodus
→ See The Kabod for a closer look at the manifestations on Sinai
40:34-38
Then the cloud covered the tent of meeting, and The Kabod YHWH filled the tabernacle.
Later in v.38 this cloud is called The Cloud of YHWH (עֲנַן יהוה). The Kabod YHWH fills the Tabernacle, and the cloud in which The Kabod dwells arises from the Tabernacle whenever the Israelites move from place to place. The cloud appears as a cloud during the day, but is filled with fire at night, completely overlapping with the previous theophany in the Exodus wandering [13:21].
Exodus Summary
YHWH appeared visibly in Genesis as The Mal'ak (God in the form of a man or an angel). In Exodus He appears in a new form: The Kabod (often translated "glory," as in the "Shekinah Glory"), a manifestation of fire or unearthly light [3:2-8; 16:10; 19:3—32:15] who came first within the Burning Bush, then in the Wilderness of Sin, culminating in the great Theophany sequences of Sinai, and then continuing for centuries as the Indweller of the Tabernacle and then the Solomonic Temple. Throughout Exodus YHWH visibly appears [5] times, [3] in discrete instances, and [2] habitually (throughout the entire Wilderness journey as cloud and fire, first independently and later over the Tabernacle). In Genesis He appeared to individuals, and this is done one last time at the Burning Bush. But after God promises to redeem the sons of Israel with an outstretched arm [6:6] He starts appearing to multitudes and whole nations, beginning with the Ten Plagues of Egypt: this is done so His Name will be known through all the Earth [9:15]. In the most memorable theophany, YHWH appeared visibly as a "devouring fire" on Mount Sinai and instituted a new covenant of the Law. Understanding who The Kabod is in Exodus provides plenary background to ill-understood New Testament verses like John 1:23, John 12:41, Acts 7:2, Ephesians 5:14, and Revelation 21:23.