Now, all believers are Born Again by the Holy Spirit.   However, the birth of this perfect Spirit being does not manifest in the soul or the body immediately.   

They are not totally In Christ though they are saved.   

For one thing they are ignorant.   

For another thing they are immature.   

For another thing they may not be completly converted.   

What do I mean by "not completely Converted"?   
I mean they have not willingly acknowledged and surrendered every area of Self Will.   

When a person totally surrenders to the person of the Holy Spirit (our comforter, our teacher, our helper and our power) they sink into Christ to be absorbed by the God Head.   

Mostly this state is an act of will but a certain amount of knowledge and strength of relationship is also required.   

How much?   ask God.   

You have to know what you are doing to make a legitimate decision.   God knows your heart and judges fairly and rightly.   

So, just soeaking "I surrender all" does not sign the contract.   

Peter told Jesus he would never deny Him and then turned around and denied Him vociferously.   Peter was not In Christ at that time.   

On the Day of Pentecost Peter was In Christ and remained so throughout his martyrdom.