Open Exodus 13:17-22.
National leaders love to be seen out in front of their nation, leading their people. But what if your king is invisible? Released from Pharaoh, Israel has a king who cannot be seen and cannot be represented by any visible carved image. How on earth do you follow a ruler like that?
Sure, they have Moses, but Moses isn’t a king: he’s merely a prophet (a spokesman for the king). Later Joshua leads them in the conquest of Canaan, but Joshua is still just a servant of their Commander-in-Chief (Joshua 5:13-15). Once Joshua dies, Israel constantly struggles to cope without a human king (Judges).
But right now, in the exodus, Israel’s invisible sovereign reveals himself to his people in a way they can see. He’s cloaked in a cloud, so they can follow where he leads.
Exodus 13:21–22 (ESV)
21 And the Lord went before them by day in a pillar of cloud to lead them along the way, and by night in a pillar of fire to give them light, that they might travel by day and by night. 22 The pillar of cloud by day and the pillar of fire by night did not depart from before the people.
This pillar-shape is what Israel might expect for a cloaked figure. While they can’t see him, they can see he’s with them. Even when darkness falls, they can still see the glowing cloud that contains his presence, something like the flame-lit pillar of smoke that hovers above a fire.
This cloud of God’s presence features through the Exodus story (13:21-22; 14:19-24; 16:10; 19:9, 16; 24:15-18; 33:9-10; 34:5). In fact, the whole Exodus narrative culminates with the king’s glorious presence taking up residence in the sanctuary they created for him (40:34-38).
The cloud is much more than a comforting, warm-and-fuzzy representation of God’s presence. The ever-present sovereign is here to lead, instruct, guide, and direct his nation. The whole point of building him a throne is so he can continue to do precisely that (25:22). In the end, following their cloud-cloaked sovereign is what defines them (40:36-38).
Consequently, it’s not surprising to see the cloud image persisting throughout the Old Testament (e.g. Numbers 15:42; 1 Kings 8:10-12; Psalm 97:2; Ezekiel 1:4; Daniel 7:13), and on into the New. God speaks from the cloud (Luke 9:35). Jesus is taken up onto the cloud (Acts 1:9). Paul sees the cloud as the divine presence (1 Corinthians 10:1-2). The sovereign who reigns in the heavens continues to lead and guide those who recognize his kingship over the earth.
That’s how the kingdom of God works. The kingdom of God is the community of people who follow the divine sovereign, so his will is done on earth as it is in heaven.