Think about this:
Jesus told His disciples who had remained after He was crucified to wait for the Promise of the Holy Spirit. Why? So that they would be His witnesses in all the world. And what do witnesses do? The testify. They speak. They speak what?
Witnesses speak that which they have personally perceived with their senses—what they have seen, what they have heard, what they have tasted and what they have felt. They speak of these things. (The alternative to a fact witness is the so-called “expert” witness who is allowed to give an opinion only based upon educational knowledge, training, and experience in a special field of study.)
Now, for Jesus, it is necessary for His witnesses to testify by the Holy Spirit. Why?
So that they do not have to be, in fact are not expected to be, experts. They speak with authority from first-hand knowledge and personal perception of the facts.
Now think: What happened at the appearance of the Holy Spirit after Jesus came up out of the water of John’s baptism at the beginning of His earthly ministry?
A voice was heard from heaven testifying of Him. “This is My Son…” And that is God’s message still today! That the world may know that the Father has sent the Son, and that they are One. (Jesus was certainly aware of the Sh’ma Yisrael! Yet He spoke shamelessly and forthrightly about being One with the Father. And the religious leaders who wanted to—and did—kill His human body knew what He was saying! See Deuteronomy 6:4; John 10:30; and then, re-read John 17:20-21.)
That is the purpose of the baptism in the Holy Spirit; that we would have that first-hand knowledge—if that is our one and singular desire in all the world—of that same message from the Father to testify of the Son while knowing personally the Holy Spirt (all three in One) just as clearly as the disciples knew and walked with Jesus, telling all the world in the tongues of angels and of men of various nations that Jesus Christ is Lord, God’s Son in whom God is well pleased, doing the Will of the Father, fulfilling His purposes. He has not abandoned us! Immanuel is with us as He said He would be, even to the end of the age. (Look again at the Good News from Matthew. He starts with and ends with the message, “God with us.”) Let us walk with Him and learn from Him as His disciples had walked with Jesus each day.
That He may have preeminence! That Christ be all in all. That is why He sent the Holy Spirit and has in these last days poured out His Spirit upon all flesh that our sons and daughter would prophesy—speaking the Word of God. Receive what He has freely given.
Then, let us testify not as mere experts, but as witnesses!
Come, let us worship Him in the splendor of His holiness and sing, sing with all that is within us. Raise your voice, “O Lord, my God, when I in awesome wonder, consider all the worlds Thy hands have made…. How Great Thou Art!”