We have no more access to God than we have by the Holy Spirit because there is a principle in the Godhead. The One who is sent as the representative must be honored if one is to have access to the Godhead. So, when the Father sent the Son, He said, “From now on, no one comes to Me except through the Son. You cannot bypass My representative and come to Me because, in every situation and circumstance, I uphold the One whom I have sent.”
When Jesus had finished His task on earth and had returned to the Father, the Father and the Son sent the Holy Spirit. The same principle applies again. We have no access to the Father and the Son except by the Spirit. We cannot bypass the Spirit and come to the Father or to the Son.
For through Him [Jesus Christ] we both [Jews and Gentiles] have access by one Spirit to the Father. (Ephesians 2:18)
We cannot leave out the Holy Spirit and still have access. Many Christians focus on the fact that we have access to God through His Son, Jesus. That is perfectly true, but it is not the whole truth. It is through the Son, by the Spirit, to the Father. Likewise, the Father indwells us when we are in the Son, through His Spirit. In each direction, whether we are going to God or whether God is coming to us, the Spirit is an essential part of the equation. We have access in the Son through the Spirit to the Father. The Father indwells us when we are in the Son through the Spirit.
If we leave the Holy Spirit out of that equation, we have no access to God, and God has no access to us. We are totally dependent on the Holy Spirit.