Nesivos Shalom: If the whole point of the klalot was to instill fear, why does Moshe appease them and tell them not to worry?

In Ekev, it commands us to circumcise our hearts, in Nitzavim it says Hashem will do so. Why the switch?

Reconciling the two opinions whether "כי המצוה הזאת" is Torah or Teshuva

The connection between the Akeida and Rosh Hashana