We had several questions texted to us during the sermon on the Holy Spirit. This is another of those questions.
Was the Holy Spirit in the Old Testament or was it brought when Jesus died?
As a member of the Triune God the Holy Spirit is eternal (always existed), omniscient (all knowing), and omnipresent (everywhere). The first time we encounter the Holy Spirit is in the second verse in the Bible (Genesis 1:2) as the Holy Spirit is active in the creation of the world. From this point on the Holy Spirit is performing His work, but His relationship with people changes after the cross.
In the Old Testament the Holy Spirit speaks to people, comes upon people, speaks through people, and does mighty works in people. But the key difference is that the Holy Spirit does this work without becoming an indwelling and eternal presence in the life of the individual. When David repents for his sin with Bathsheba he cries out to God asking Him not to take the Holy Spirit from him (Psalm 51:11).
As Jesus is teaching on this in John 14:16-18 he tells His disciples that they know the Holy Spirit because He has been with them, but will soon (after Jesus death and ascension) He will be in them. The difference from the Old to the New Testament is the difference of the Holy Spirit being with people and the Holy Spirit setting up residence within followers of Jesus. In another place Jesus describes this event as being baptized in the Holy Spirit (Acts 1:4-5). The word Greek word baptizo means to immerse or submerge. In other words, Jesus is promising a point in which the Holy Spirit will indwell the follower of Jesus in such a way that he fills us and we are immersed in Him. This level of relationship is made available because of the substitutionary atonement and forgiveness of Jesus. Jesus death allows for a different level of relationship with God in the person of the Holy Spirit.
So, the Holy Spirit has always existed, and was at work int he Old Testament. But our relationship with Him is deeper and greater because of the work of Jesus on the cross. To God be the glory forever!