Ramban

AND NOW GO, LEAD THE PEOPLE. [G-d is saying here:] “Since I have repented from destroying them, lead them unto the place of which I have spoken unto thee — to the place of the Amorite, the Canaanite, etc.” However, He did not want to mention this expressly, for this was said in a manner of anger, as if to say: “What I have said to you, I shall do in your honor, but I will not forgive them their sin, for in the day when I visit, I will visit their sin upon them — I will visit it upon them even after they come to the Land.” This was an allusion to the time of the exile, or to what our Rabbis have said that “No punishment [ever comes upon Israel] in which there is not a small part for the sin of the golden calf.”