God has no 'voice' because God has no physical body to create sound with. Do not expect to hear with your ears. You hear with your heart. It is more a feeling of just 'knowing' as opposed to actually hearing a sound. This makes it extremely difficult because we often have our own 'inner voice' that speaks to us. How can we tell which is us and which is from God? There is no way to know for sure. It is all hinged on FAITH.