On the day that - that is, “at the time that,” . The presentation of the gifts in fact occupied twelve days, as the sequel shows.

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And it came to pass on the day that Moses This was the second contribution of the people, after the completion of the Tabernacle. Although…

And it came to pass on the day that Moses had fully set up the
tabernacle
Not on the …

The offering of the princes for the service of the tabernacle was not made until it was fully set up. Necessary observances must always take preced…