Translation:Mikraot Gedolot/Numbers/1:1

Text
The Lord spoke to Moses in the wilderness of Sinai, in the Tent of Meeting, on the first day of the second month, in the second year after they came out of the land of Egypt, saying:

Rashi
''And He spoke... in the wilderness of Sinai... in the Tent of Meeting...''

Because they are so beloved to Him, he counts them frequently:
 * He counted them when they left Egypt (Exodus 32:28);
 * He counted them when they fell regarding the [golden] calf (Exodus 38:26), to know how many were left;
 * [And here] when he was about to let His presence dwell among them, he counted them.

The Tabernacle was set up on the first day of Nissan (Exodus 40:17), and on the first day of Iyyar He counted them.

Ibn Ezra
in the wilderness of Sinai

To let us know that Moses only ascended Mount Sinai after the Glory was present in the Tent of Meeting.

on the first day of the second month

To institute the "banners," how they should travel and how they should camp, for the sake of the Sanctuary, for they traveled on the twentieth day of the second month.

Ramban
Because He interrupted [the flow of Commandments given at the Tent of Meeting] with the Ordinance of the sabbatical year and jubilee, which they said were [given] on Mount Sinai (Leviticus 25:1), He repeated and said here that this statement was [given] at the Tent of Meeting, like all statements that were mentioned since the beginning of the book of Leviticus. And so will they all be [given] from now on at the Tent of Meeting; for ever since the Tabernacle was erected, and the Lord called him from the Tent of Meeting, He only spoke with him from there.

He mentioned here in the wilderness of Sinai, to tell us that they only moved from there after they were counted, for the second counting (Numbers 26:3) was in the plains of Moab, and the Commandment [for that count was given] in the Tent of Meeting.

Rashbam
in the wilderness of Sinai in the Tent of Meeting on the first day of the second month

In all the Commandments given in the first year before the Tabernacle was erected, it is stated "on Mount Sinai." But since the Tabernacle was erected on the first day of the [first] month of the second year, Mount Sinai is not mentioned, but rather "in the wilderness of Sinai in the Tent of Meeting."

This can be proven from the following [verses], thus: "These are the descendants of Aaron and Moses on the day the Lord spoke with Moses on Mount Sinai" (Numbers 3:1), before the Tabernacle was erected, then the descendants of Aharon were four: "These are the names of Aharon's sons: the firstborn, Nadav; Avihu, Eleazar and Itamar" (Numbers 3:2).

But in the end, in the second year when the Tabernacle was erected, they were but two, since in the end, when the Tabernacle was erected in the second year, it is stated: "Nadav and Avihu died in front of the Lord etc. in the wilderness of Sinai" (Numbers 3:4): in the wilderness of Sinai they were four and then two, as on the very day the Tent of Meeting was erected, Nadav and Avihu died.

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