John Gill Commentary Deuteronomy 4:21

"Furthermore Jehovah was angry with me for your sakes, and sware that I should not go over the Jordan, and that I should not go in unto that good land, which Jehovah thy God giveth thee for an inheritance:" — Deuteronomy 4:21 (ASV)

Furthermore the Lord was angry with me for your sakes
See (Deuteronomy 3:26) :

and swore that I should not go over Jordan ;
this circumstance of swearing is nowhere else expressed:

and that I should not go in unto that good land ;
the land of Canaan; he might see it, as he did from Pisgah, but not enter into it:

which the Lord your God gives you for an inheritance ;
to them and to their children after them.