God speaks to humans. God is spirit. He communicates to our spirits. We hear God with our heart. The level of communication (how much he speaks and how much we hear) between us and God depends on the depth of our relationship with him.
There are different ways God speaks to man.
To the carnal fallen man, God speaks through the man’s conscience
To His own Children, God speaks through His Spirit in them
Indirectly, man can hear God’s words through written texts (Bible and other Christian literature) and through the voice of his children.
1) Through His Spirit
When God speaks in the heart, his voice is quiet and wordless, but the message is understood by the hearer. His children get to know him easily because they hear and see him. The ears and eyes of their hearts have been opened to receive. Revelational knowledge comes without rigorous bible study. With a single scripture, comes a string of understanding and knowledge that seems like an overflow. The mind is illuminated to understand and know. We receive intuitively. Intuition is quick and direct insight. This intuitive ability comes when the ears and eyes of our spirit are opened by Christ Jesus. Many hear and hear, but perceive not. Many look and look, but cannot comprehend. They can not understand or know because they are not united to the Spirit of Christ.
2) Through the conscience
Every man has a conscience because every man is in the first Adam. The first Adam ate of the tree of knowledge of good and evil. Every man has the ability to know good and evil. This tree of knowledge is the spirit of God and it is God’s voice. However, in sinfulness, the conscience can lose its guide or be dulled. All mankind will be judged by their deeds, because all knew right from wrong.
3) God’s Written Word and voice of His children
From written words and the voice of his children, we can only hear God’s word indirectly (not his direct voice). God’s word is profitable because it will show us the way to him. God uses his written words to illuminate our minds when he speaks to our spirit.
Amidst many voices, the perfect way to discern the voice of God is through His Spirit, on the foundation of the written word. If we hear Him directly, we will clearly discern which voices of men are the mouthpiece of God or of the devil. To hear Him directly, we need to become followers of Christ, united to the Spirit of Christ. People who are not his disciples can be easily deceived by the enemy because they are not in the Spirit of Christ.