We sense it.
Your spirit, not your mind or body is always first to know everything. You sense in your spirit what is right. You sense in your spirit what is wrong. When something is of God, your spirit agrees with the Spirit of God, that it is God. Your spirit is the one true indicator. Let me ask you, "do you really trust your body to always tell you the truth or to do what is right?" "Do you really trust your mind to always think the right thoughts or to make the right decision?" Ouch!!!
Excerpt from The Power of God Thinking by Keith C. Powell Copyright 2010