Ibn Ezra on Exodus 20:16/אבן עזרא על שמות כ׳:ט״ז

1AND THEY SAID. The reference is to the priests and the heads of the tribes who were close to Moses. They spoke to Moses after the Ten Statements were completed because they were very anxious, for they feared that God would continue to speak to them and that they would consequently die. That is why Moses told them, Fear not (v. 17).