Habakkuk knew how to hear the voice of God:
"I will stand my watch ("mishmereth" - watch, i.e. the act of the sentry) and set myself on the rampart, and watch to see what He will say to me, and what I will answer when I am reproved. Then the LORD answered me and said: "Write the vision and make it plain on tablets, that he may run (with it -- obedience) who reads it." (HAB 2:1-2)