Knowing what God really thinks, His heart, His will, His purpose, is very critical to having a positive working relationship with Him.
1 Corinthians 2:11-12 NIV
 For who knows a person's thoughts except their own spirit within them? In the same way no one knows the thoughts of God except the Spirit of God.  What we have received is not the spirit of the world, but the Spirit who is from God, so that we may understand what God has freely given us.
So what are you really thinking? Your spirit only really knows. There are certainly impressions you have made, things you’ve said and things you’ve done that have given people an opportunity to develop their own perception about what’s going on in your mind. But, do they really know, and how often is what they come up with really a misperception? Quite often the basis for determining what is going on in your head is the pattern of thinking already developed in the mind of the one making that determination. If a certain thought is what they would have in response to a situation, then surely that is what you’re thinking also. While there will be some success with this approach, those times when it fails can have a devastating impact on relationships and ability to work together. Because, only your spirit knows what you’re really thinking.
Knowing what God really thinks, His heart, His will, His purpose, is very critical to having a positive working relationship with Him. A perception of His thoughts based upon how we’ve become accustomed to thinking in the world is wrought with probability of error. Even our interpretation of how His Word represents His thoughts, if coming from a worldly pattern of thinking, will be skewed from reality. It will not be possible to even effectively believe something about God that is based upon our own pattern of thinking. Because, only the Spirit really knows His true thoughts.
How amazing it is, then, that in the gift of the Spirit is also a window and entrance into the true thoughts and intents of our amazing Father God. To be filled with the Spirit, and to be yielded completely to His influence is to be enabled to really understand what He has already freely given us and what His thoughts are towards us. Again, this is not possible coming from our own worldly pattern of thinking, but only by the Spirit. There is, though, a continually opportunity to not be conformed to the world, but be transformed from those old perceptions of Him to true and productive ones. Because, only the Spirit knows the true thoughts of the Father, and we’ve been given the Spirit.