What does Matthew 4:8 mean?

Matthew 4:8 KJV
Again, the devil taketh him up into an exceeding high mountain, and sheweth him all the kingdoms of the world, and the glory of them;

Matthew 4:8 NKJV
Again, the devil took Him up on an exceedingly high mountain, and showed Him all the kingdoms of the world and their glory.

Matthew 4:8 MKJV
Again, the Devil took Him up into a very high mountain and showed Him all the kingdoms of the world and their glory.

Matthew 4:8 KJV 2000
Again, the devil took him up into an exceedingly high mountain, and showed him all the kingdoms of the world, and the glory of them;

Interlinear KJV

Again, /palin/ the devil /diabolos/ taketh /paralambano/ him /autos/ up /paralambano/ into /eis/ an exceeding /lian/ high /hupselos/ mountain, /oros/ and /kai/ sheweth /deiknuo/ him /autos/ all /pas/ the kingdoms /basileia/ of the world, /kosmos/ and /kai/ the glory /doxa/ of them; /autos/

Albert Barnes’ Commentary

Verse 8. An exceeding high mountain. It is not known what mountain this was. It was probably some elevated place in the vicinity of Jerusalem, on the top of which could be seen no small part of the land of Palestine. The Abbe Mariti speaks of a mountain on which he was, which answers to the description here. “This part of the mountain,” says he, “overlooks the mountains of Arabia, the country of Gilead, the country of the Arnorites, the plains of Moab, the plains of Jericho, the river Jordan, and the whole extent of the Dead Sea.” So Moses, before he died, went up into Mount
Nebo, and from it God showed him “all the land of Gilead, unto Dan, and all Naphtali, and the land of Ephraim, and Manasseh, and all the land of Judah, unto the utmost sea, and the south, and the plain of the valley of Jericho, the city of palm trees, unto Zoar,” De 34:1-3. This shows that there were mountains from which no small part of the land of Canaan could be seen; and we must not suppose that there was any miracle when they were shown to the Saviour.

All the kingdoms of the world. It is not probable that anything more here is intended than the kingdoms of Palestine, or the land of Canaan, and those in the immediate vicinity. Judea was divided into three parts, and those parts were called kingdoms; and the sons of Herod, who presided over them, were called kings. The term world is often used in this limited scale to denote a part, or a large part of the world, particularly the land of Canaan. See Ro 4:13, where it means the land of
Judah; also Lu 2:1, See Barnes “Lu 2:1”.
The glory of them. The riches, splendour, towns, cities, mountains, etc., of this beautiful land.