These verses are parenthetical. They interrupt the narrative of what Moses did “on the first day of the first month,” informing us of the use to wh…

When they went into the tent of the congregation
Not only at this time, but at all other times:

a…

When the tabernacle and its furnishings were prepared, they did not delay setting it up until they came to Canaan; but, in obedience to the will of…