The Trinity represents the three offices of God; He uses each of them in a special way to communicate with you and these three offices should not be confusing to you when Christ in John 10:30 KJV says:
I and my Father are one.
The Holy Ghost (Spirit) completes God’s three offices and in 1 John 5:7 KJV Christ continues to remind you that they are one:
For there are three that bear record in heaven, the Father, the Word, and the Holy Ghost: and these three are one.
So now we have it, God our creator, Christ His Son who represents Him in the flesh and The Holy Spirit are one and the same. The Holy Spirit is simply the office that God uses to be with us until Christ returns; it is the office or Spirit of Christ.
In John 14:11 KJV, Christ makes a special appeal for you to believe and understand that the three are one:
Believe me that I am in the Father, and the Father in me: or else believe me for the very works' sake.
The works of Christ are seen by us and here He asks that we take a close look at them to gain an understanding that His Works are the works produced by His Father. This point could not be made any clearer than Christ does when He reminds us that being in His Father and His Father being in Him makes them one and the same.
Taking a closer look at the third member of the Trinity, the Holy Spirit, we go to Acts 2:33 KJV:
Therefore being by the right hand of God exalted, and having received of the Father the promise of the Holy Ghost, he hath shed forth this, which ye now see and hear.
Returning to His Heavenly Father 2000 years ago, the Holy Spirit, the third office of the Trinity, is the office used by Christ to be with you now. This office is real; you feel it, you feel the presence of Christ, even though He is with His Father in Heaven.
Scripture plays a big part of His presence; it is how God enables you to see hear and feel Christ; it is the Holy Spirit at work. John 14:18 KJV shows Christ coming to you through this third office:
I will not leave you comfortless: I will come to you.
Not leaving you comfortless is Christ sharing Himself with you through the office of the Holy Spirit and in John 14:26 KJV, you observe God addressing the Holy Spirit and His other two offices:
But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.