Moshe wanted to enter the Land of Israel because he foresaw with prophecy that in the end of days the verse will be fulfilled ‘Then I will convert the peoples to a pure language that all of them call in the name of the Lord, to worship Him of one accord.’
That is why Moshe wanted to enter Israel, to bring close those that are far, and usher them under the wings of the Shechina, just as he began to do this during the Exodus from Egypt, taking a large multitude of Egyptians with him because he wanted to bring those alienated close.
This is what he meant ‘I beseeched to G-d,’ that his prayer was not on his own behalf it was on behalf of G-d, to make all serve Him on one accord as will indeed be in the future...
But to this G-d answered, ‘You already have much.’ This refers to what it says in the Medrash (Devarim Rabbah 7:5): ‘You shall be blessed when you come and you shall be blessed when you depart’ ‘When you come in’ refers to when Moshe entered this World and he brought close the distant, meaning Basya daughter of Pharaoh who converted. ‘When you depart’ refers to when Moshe left this World, and he brought close the distant referring to Reuben. So, G-d is answering him, “You want to enter Israel in order to bring those that are distant close, ‘you already have much,’” meaning, you already brought many close [to G-d] both with your birth and with your passing!”
This is hinted to in the word [‘you already have] much’, in Hebrew, ‘rav’, רב. This is an abbreviation for Reuben and Basya. Reuben when you left (this world), Basya when you came (into this world).
Another thing hinted to in the word ‘rav’ is the mixed multitude of Egyptians, ‘eirev rav’, who Moshe took with him and tried to usher them under the wings of the Divine Presence, but was not successful. Therefore, G-d said, ‘Do not add another word’ but showed him at the end of days when this will indeed occur. That is what is meant ‘Go up to the top of the peak,’ that G-d showed him the Moshiach.
