“The promises and warnings Hebrews are especially relevant for us in the 21st century. We might think that those who heard Jesus speak and saw him perform miracles have a greater responsibility than we who have met him only through the words of Scripture. Hebrews argues the opposite, however. The readers did not hear God speak at Mount Sinai or Jesus while on earth (2:1–4); yet, they have greater responsibility because they hear God's voice speaking to them through Scripture. This is, in my view, the most striking teaching of Hebrews regarding obedience. Hebrews places the authority of Scripture over the authority of sense experience. What you ‘hear’ through Scripture is more authoritative than what you see, touch, hear, or taste through the senses.”
Felix H. Cortez, “‘See That You Do Not Refuse the One Who is Speaking’: Hearing God Preach and Obedience in the Letter to the Hebrews,” Journal of the Adventist Theological Society 19 (2008): 107–8.