Bible Notes Online - Numbers 2 - ESV
Commentary

The armies, now numbered, were set in order in the camp.

v1-2: The people of Israel had to camp around the tabernacle, but some distance from it.

v3-9: On the east side, Judah, Issachar, Zebulun, all children of Leah; totalling 186,400 men. These tribes would set out first when the people moved.

v10-16: On the south side, Reuben, Simeon, Gad, children of Leah, and Zilpah (Leah's concubine); totalling 151,450 men.

v17: The Tabernacle, with the Levites attending it, travelled in the middle of the people.

v18-24: On the west side, Ephraim, Manasseh, and Benjamin, all children of Rachel; totalling 108,100 men.

v25-31: On the north side, Dan, Naphtali, and Asher, children of Bilhah and Zilpah; totalling 157,600 men. The relevance of the separation of the children of Leah from the children of Rachel may be to avoid any ongoing animosity.

Note too the order of the tribes, and their names, demonstrates the work of the Holy Spirit in God's people;

First, Judah, meaning "praise"; where we must start, in praising God;

Second, Reuben, "see, a son", testifying of Christ, which is the primary work of the Holy Spirit.

Third, Ephraim, "fruitfulness", the result of following and obeying Christ.

Finally, Dan, "judgement", for the Holy Spirit brings conviction, John 16.7-11.

v32-33: The numbering of Israel excluded Levi.

v34: The Israelites did not break camp at this point; rather this was the order they were to march and camp later. What was important, as in 1.54, was that they obeyed what God had said through Moses.