I might think it was given at night; it is, therefore, written (Ibid. 19:16) "And it was on the third day, when it was morning, etc." I might think that it was given in silence; it is, therefore, written (Ibid.) "and there were thunders and lightnings." I might think that they did not hear the thunders; it is, therefore, written (Ibid. 20:15) "And all the people saw the thunders and the lightnings," and (Psalms 29:4) "the voice of the L–rd in majesty, etc."