John Gill Commentary Deuteronomy 1:3

"And it came to pass in the fortieth year, in the eleventh month, on the first day of the month, that Moses spake unto the children of Israel, according unto all that Jehovah had given him in commandment unto them;" — Deuteronomy 1:3 (ASV)

And it came to pass in the fortieth year
That is, of the coming of the children of Israel out of Egypt:

in the eleventh month ;
the month Shebet, as the Targum of Jonathan, which answers to part of January and part of February:

in the first day of the month, that Moses spoke to the children of
Israel according to all that the Lord has given him in commandment to
them ;
repeated to them the several commandments, which the Lord had delivered to him at different times.