Rashi on Ki Sisa 34:30

English: וייראו מגשת אליו AND THEY WERE AFRAID TO STEP NIGH UNTO HIM — Come and see how great is the power (influence) of sin! For before they streched forth their hand to sin what does Scripture say? (Exodus 24:17) “And the sight of the glory of the Lord was like devouring fire on the top of the mountain in the eyes of the children of Israel”, — and yet they were not afraid and did not tremble! But after they made the golden calf they recoiled and trembled even at the sight of the rays of glory of Moshe! (Sifrei Bamidbar 1:8)