John Gill Commentary Numbers 27:12

"And Jehovah said unto Moses, Get thee up into this mountain of Abarim, and behold the land which I have given unto the children of Israel." — Numbers 27:12 (ASV)

And the Lord said to Moses
After the covenant made with Israel in the plains of Moab, and the song delivered to them, (Deuteronomy 29:1) (Deuteronomy 32:1–49)

get you up to this Mount Abarim ;
which was a range of mountains, so called from the passages by them over Jordan into the land of Canaan; one part of which was Nebo, and the top of that Pisgah, from where Moses had the view of the good land here directed to; see (Numbers 33:47) (Deuteronomy 32:49) (34:1) .

and see the land which I have given to the children of Israel ;
for though he was now one hundred and twenty years old, his eyes were not dim, he could see at a great distance; and the height of this hill gave him an advantage of taking a prospect of the land, a great way into it; and very probably his sight might be greatly strengthened and increased at this time by the Lord, for the purpose; this may be an emblem of that sight by faith, which believers have at times of the heavenly Canaan, and sometimes are favoured with an enlarged one of it before their death.