What is the function of the Holy Spirit in our lives?
"But when he, the Spirit of truth, comes, he will guide you into all truth. He will not speak on his own; he will speak only what he hears, and he will tell you what is yet to come." (John 16:13 NIV)
The prominent role of the Holy Spirit is to guide the believers into God's wisdom. By this wisdom, Jesus meant the truth about his identity, the truth of his words and actions, and the truth about all that would happen to him. Jesus said the "Spirit of truth" would give comfort to the believer.
In time they would fully understand that he was the Son, come from the Father, and was sent to save people from their sins. But only after these events occurred, and only through the Holy Spirit's guidance would the disciples begin to understand. The Holy Spirit is the true guide for all believers; his primary task is to instruct us about God's truth.
"But you have an anointing from the Holy One, and all of you know the truth." (I John 2:20 NIV)
The chief was God communicates with Christians is through the inward voice or our conscience. The conscience can be weakened by not following God's leading. So we need to quickly follow God's lead, not our flesh's desire.
This "truth" includes our knowing the answers to our questions and the guidance we need to function in this life. This guidance will never violate the written Word of God, the Bible. Once we accept Jesus as our savior, the Holy Spirit indwells us, and speaks to our human spirit (the inward voice) and we should respond. So we shall respond or we will deaden our conscience!