Moses smashed the stone tablets with the law on them back in chapter 32 when he came upon the people apostate. So now he and God do it all again.
The smashed law was the sign of god’s abandonment of them, now Moses take new blank tablets he made himself for God to write on. First was all God, this includes Moses’ participation.
So god makes his promise again and shows his love and compassion to precious, faithful Moses. After that Moses’ face shines, and he has to wear a veil to stop people staring.
The warnings have started about the promised land. They must not comprise with the local religions. I already know that only partially works.