I wonder sometimes why we don't hear God's audible voice today. It seems the easy thing to do to get the attention of people. When God spoke in the Bible, especially to his naughty children, the Israelites, everyone who heard it was afraid, with the exception of course, of Moses, who conversed with the voice speaking to him. When God's voice was audibly heard during the times of Jesus, there was discussion amongst the hearers of what was heard.
So now He's left us with written words...a lot of them. Without being audible they still put fear in some, humble gratitude in others, wonder and hope in many. No one can argue with how we each "hear" his word. He speaks to each of us with it, where we're at, to our unique lives. It doesn't take a booming voice, surrounded by fire, for his words to penetrate the heart. Sometimes it only takes one, two, or just a handful of words to calm an anxious heart.
Do not fear.
Do not be discouraged.
Rest in me.
Come to me.
I am always with you.
I like to think he has given us his words in a written language so that we can read it in the moment, we can go back and reread our favorite parts, like a young couple in love read the love letters over and over again. The written word speaks to the heart in a way no shouting audible voice can ever do. That's how God rolls.
Exodus - pick a spot, any spot and see how Moses conversed with the voice of God.