"On the day that the tabernacle was set up, the cloud covered the tabernacle, the tent of testimony" (Num. 9:15a). Here we see that on the day the tabernacle was set up, the cloud (the Spirit) covered (overshadowed) the tabernacle of the testimony. This overshadowing in the vast and terrible wilderness was a great salvation. Furthermore, I believe that the cloud overshadowed not only the tabernacle but the entire camp of the children of Israel. In the wilderness there was an array, and above that array was an overshadowing cloud. This overshadowing cloud was an indication, a testimony, that there was something on earth for God.
"At evening it was over the tabernacle like the appearance of fire until morning. So it was continually; the cloud covered it, and at night it had the appearance of fire" (vv. 15b-16). In typology, the cloud signifies the Spirit, and the fire, for enlightening, signifies the Word. When we have a clear sky in our spiritual life, we feel the presence of the Spirit. Quite often, however, we are in the night, and then the Spirit becomes the Word to us. This is a strong proof that the Spirit is the Word (cf. Eph. 6:17-18). The over-shadowing element becomes the shining essence. Today we have both the Holy Spirit as the cloud and the holy Word as the fire. The Holy Spirit as the cloud overshadows, and the holy Word as the fire shines.
When the cloud was taken up from over the tabernacle, the sons of Israel set out. Where the cloud settled down, they encamped. When the cloud abode over the tabernacle, they remained encamped (Num. 9:17-22). Because the children of Israel followed the cloud, they did not need to worry or be anxious about when to move. Instead of being anxious, they could be at peace.
The children of Israel followed the cloud in order to keep the charge of God according to the word of God by Moses. "At the word of Jehovah they encamped, and at the word of Jehovah they set out; they kept the charge of Jehovah according to the word of Jehovah by Moses" (v. 23).
In the wilderness, the children of Israel numbered more than two million, but they were in good order and were under a divine arrangement. They did not stay or move according to their own likes, dislikes, or preferences. Rather, they stayed together or moved together according to the word given by God to Moses.