Ephesians 2:6 For He raised us from the dead along with Christ and seated us with him in Heavenly places....

So God raised us up because we were dead in our sins, our sins was then taken by  God and put into Jesus so when Jesus was raised our sins was made right with God and we became in a righteous form to sit with Jesus at the right hand of God in heaven.

So what I'm understanding is that our spirit which does not conform to space or time is sitting with Jesus in Heaven on the right side of God the Father,

Communicating with God the Father, Jesus the Son and the Holy Spirit that lives on earth in us would mean that we would all be speaking "spirit to spirit".

I believe speaking "in spirit" is speaking in thoughts, speaking in thoughts would be the perfect way to speak to God because we would be totally Open ,transparent and completely honest to God knowing that Holy God would know our every thought before we would be able to censor it when speaking.

I also believe that when a spirit ( good or evil) speaks to us it is done using thoughts,  (speaking with our voices can also be a way to communicate with spirits.) we think we hear it coming from out side our heads but it is really coming from in side our brain.

 People who hear imaginary voices hear it coming from outside of their head, that is why they will speak back to the voices out loud but spiritual people who know that it is spirits speaking  will speak back in thoughts and will hear the spirit respond.

Speaking"spirit to spirit" with God, coming boldly to His throne, being right-standing with Holy God is every Christians dream and i believe it is being done in heaven by God, Jesus and all Christians.