Deuteronomy 1:23
And the saying pleased me well: and I took twelve men of you, one of a tribe:
More from Deuteronomy 1
These be the words which Moses spake unto all Israel on this side Jordan in the wilderness, in the plain over against the Red sea, between Paran, and Tophel, and Laban, and Hazeroth, and Dizahab.
(There are eleven days' journey from Horeb by the way of mount Seir unto Kadeshbarnea.)
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 the LORD had given him in commandment
After he had slain Sihon the king of the Amorites, which dwelt in Heshbon, and Og the king of Bashan, which dwelt at Astaroth in Edrei:
On this side Jordan, in the land of Moab, began Moses to declare this law, saying,