For more information related to this topic, check out
Bob Yandian’s book, “Understanding Your Authority in Christ.”

Thanks for the question, Charlene. It is obvious that you are a student of scripture to have noticed this. Many believers are unaware of the difference between Old Testament (OT) and New Testament (NT) issues. Because of the “work of the Cross” many things are handled differently by NT believers, than they were by those of the OT. And, it is the Life—Death—Resurrection of Jesus Christ that is the dividing line. That “event” has changed almost everything. For example:

• OT: Salvation was future—based on the “hope” of a coming Redeemer / Seed / Promise/ Savior / Messiah
  NT: Salvation is past—based upon “faith” in what GOD has done for us in the sacrifice of His Son (the Redeemer / Seed / Promise / Savior / Messiah) JESUS CHRIST
  
• OT: GOD’S presence for the believers was External & Temporary—He spoke from outside mankind / visited with them / went with them / anointed them—all from the outside “temporarily”
  NT: GOD’S presence for believers is Internal & Permanent—GOD lives within us / speaks from within / leads from within / dwells within—all with the promise that He will never leave or forsake us, and will finish in us what He has started

Those are just a couple of examples, but I wanted to point out that life for the NT believer is vastly different from that of the OT believers. All of this, because of Jesus Christ!

With that in mind, let me address your question. I will do so by showing the transition of authority from the time of the OT, through the ministry of Jesus, to the believer of the NT.

Authority in the Old Testament
Knowledge of Satan and demons in the OT was very limited. The people were aware of their presence, identity, and some of their work. But they were not told to deal with them, fight them, or bind them. The book of Job is the oldest written book of the Bible. It was written before Moses recorded the events of GENESIS. From indications, it appears that Job lived previous to the call of Abraham from Ur of the Chaldees. Yet, in this oldest of books, the very purpose and operation of Satan is presented (Satan came to steal, kill, and destroy).

So, the knowledge of Satan and his purpose was known. In Isaiah 14:12–17, and in Ezekiel 28:11–19 we have the record of his creation, sin, and fall. And of course in Genesis 3:1–19 we have the account of his temptation of Eve, then Adam, GOD’S curse upon him, and the declaration of his ultimate defeat.

Knowledge of demons is not so well presented in the OT, but it is certain that they were known, and their works were feared by all. The pagan nations tried to appease them by the creation of religions that appealed to their possession and manipulation of mankind (especially women and children). The followers of Jehovah struggled against them, resisting the demonic desires to follow sinful and carnal ways, and they physically fought against the followers of the demonically influenced religions—nations cursed by GOD for their yielding to the flesh and sin.

But, as to how to deal with the demons, there was no instruction. WHY? The OT believers, be they priests, prophets, kings, warriors, or any other individual did not have authority in the realm in which they operated. All mankind could do was resist / fight them in the natural realm. This limited them to fighting flesh and blood enemies. They were not able to deal with the “power” behind the enemy—that being Satan and demonic authorities. But, again, WHY?

Consider a couple of passages from the OT. These will give some insight into the answer.

• ZECHARIAH 3:1:
  Then he showed me Joshua the high priest standing before the angel of the LORD, and Satan standing at his right hand to accuse him. 2 The LORD said to Satan, "The LORD rebuke you, Satan! Indeed, the LORD who has chosen Jerusalem rebuke you! Is this not a brand plucked from the fire?"
  
  It was the Lord who spoke to Satan—He alone had the power to rebuke him. It wasn’t Joshua the High Priest, nor the Prophet Zechariah who had any power over Satan, only GOD Himself.
  
  The OT scriptures consistently declare that it was GOD who rebuked evil:
  • “Thou hast rebuked the nations, Thou hast destroyed the ungodly” Psalm 9:5.
  • “Thou hast rebuked the proud, accursed” Psalm 119:21.
  • “They perish at the rebuke of Thy Countenance” Psalm 80:16.
  • “At Thy rebuke, O GOD of Jacob, both the chariot and horse are cast into a deep sleep” Psalm 76:6.
  • “GOD shall rebuke him, and he fleeth far off, and shall be chased as the chaff of the mountains before the wind” Isaiah 17:13.
  • “He rebuked the Red Sea and it dried up” Psalm 106:9.
  • “The foundations of the world were discovered at Thy rebuke, O LORD” Psalm 18:15
    
• JUDE 1:9:
  But Michael the archangel, when he disputed with the devil and argued about the body of Moses, did not dare pronounce against him a railing judgment, but said, "The LORD rebuke you!"
  
  Although this is recorded in the NT, it took place at the end of the Book of DEUTERONOMY. When the Archangel carried Moses body to heaven, even he did not have the authority to “rebuke” Satan. He invoked the LORD’S authority.
  
• DANIEL 10:10–14:
  10 And, behold, an hand touched me, which set me upon my knees and upon the palms of my hands. 11 And he said unto me, O Daniel, a man greatly beloved, understand the words that I speak unto thee, and stand upright: for unto thee am I now sent. And when he had spoken this word unto me, I stood trembling. 12 Then said he unto me, Fear not, Daniel: for from the first day that thou didst set thine heart to understand, and to chasten thyself before thy God, thy words were heard, and I am come for thy words. 13 But the prince of the kingdom of Persia withstood me one and twenty days: but, lo, Michael, one of the chief princes, came to help me; and I remained there with the kings of Persia. 14 Now I am come to make thee understand what shall befall thy people in the latter days: for yet the vision is for many days.

In this passage while Daniel has been in prayer, the angels were wrestling in the heavenly realm. Daniel, himself, had no authority to deal in that realm, but Michael, the Archangel finally came to assist, and released the angel to deliver the message to Daniel.

When Joshua, Gideon, David, etc. were sent to conquer in the Name of Jehovah, they had to fight “flesh and blood” enemies—they had to fight people. They could not engage the demons, or Satan himself. They had no power in that realm—no authority.

Authority During Jesus’ Ministry
From the beginning of Jesus’ ministry there was a notable change. He did things differently than anyone had ever seen. Yes, they had seen miracles, healings, even people “delivered” from demons. But, never had the power to do so been at the authority of a man!

• MARK 1:21–28:
  (vs. 27) They all were amazed, so as to question among themselves, saying, What is this? What new doctrine is this? For He even commands the unclean spirits with authority, and they obey Him.

This is the very first miracle of healing / deliverance performed by Jesus. What a glorious declaration—this is what GOD wants! Jesus had announced his anointing and the purpose of it in the Synagogue of Nazareth. He said: “The Spirit of the Lord is upon me, because He has anointed me…” (LUKE 4:18).

Notice that what surprised them was not that the man was delivered. Obviously they had seen people who had been oppressed / possessed by demons, and been delivered by exorcism. The people were accustomed to the use of magical formulae by the Jewish exorcists (MATTHEW 12:27; ACTS 19:13), but this was something utterly different. Later, Simon Magus could not understand how Simon Peter could do his miracles without some secret trick and even offered to buy it (ACTS 8:19). This is the same surprise / wonder that existed in Jesus’ ministry. Jesus spoke with authority and the demons came out—they obeyed Him! That’s new; that’s different. He didn’t ask GOD to it; He didn’t chant some formula; He didn’t beg the demons. He cast them out—and they obeyed!

• ACTS 10:38:
  …how GOD anointed Jesus of Nazareth with the Holy Spirit and with power, and He went about doing good, and healing all those who were oppressed by the Devil, for GOD was with Him.

It must be made clear that what Jesus did as He ministered during his three years was not done because He was the Eternal Son—GOD Himself. Truly He was, but that was not the source of His power to heal and deliver. This power / authority came from his “anointing” not from His deity. Most theologians do not recognize this, and thereby give little place to it, but that is the declared fact. He was a “man” anointed by the Holy Spirit. And that is what figures into our discussion.

During Jesus’ ministry on earth He showed that a “transition” was taking place. Because of who He was, and what He was going to do (the perfect sacrifice), man would no longer live in subjection to and the fear of the devil. His 3 years of ministry showed mankind what the Messiah was going to do: Set mankind free from the bondage of sin and death. Once free, they could live in a new realm. They would have a new life, a new relationship to GOD, a new destination, and a new authority.

• LUKE 10:19–20:
  Behold, I give to you authority to tread on serpents and scorpions, and over all the power of the enemy. And nothing shall by any means hurt you. 20 Yet do not rejoice in this, that the evil spirits are subject to you, rather rejoice because your names are written in Heaven.

Even as He walked the earth, He had shared His authority with those who followed Him. They had gone out and found that the same “power” was evident in their ministry. It wasn’t permanent with them until after Pentecost, but it was there. He declared that they had received “authority – exousia (delegated authority)” over all the power – dunamis (inherent / even supernatural ability)” of the devil. It was no longer a matter of asking God to deal with the devil, or waiting for an angel to deliver a “rebuke” to Satan. They had authority.

Jesus’ authority was evident in many dimensions of his ministry. He rebuked demons; fever; the wind; the words of Satan. He was demonstrating that through His anointing as the Messiah mankind would find a new place of freedom—authority in this world.

The Authority of the New Testament Believer
Jesus’ ministry was a model for all those who follow Him. In JOHN 14:12 He commanded His disciples, “The one who has faith in me will be doing the works that I have done and greater works because I am going to my Father” (NIV). He then went on to teach about the indwelling presence of the Holy Spirit who would lead us, teach us, and enable us. Then, in His final commission to His disciples, and all who follow him, Jesus revealed the results of our newly found relationship through the New Birth.

• MARK 16:16-18:
  And He said to them, Go into all the world, proclaim the gospel to all the creation. 16 He who believes and is baptized will be saved, but he who does not believe will be condemned. 17 And miraculous signs will follow to those believing these things: in My name they will cast out demons; they will speak new tongues; 18 they will take up serpents; and if they drink any deadly thing, it will not hurt them. They will lay hands on the sick, and they will be well. 19 Then indeed, after speaking to them, the Lord was taken up into Heaven, and sat on the right hand of God. 20 And going out, they proclaimed everywhere, the Lord working with them and confirming the Word by miraculous signs following.

One of the marks He listed as a sign of our “believing” was the authority to “cast out demons”. It was because of the authority of “His Name”. This was different from the authority of the OT believers. They had to use physical power against those who were motivated and empowered by demonic influences. The NT believers, however, would have “authority” over the power of the demons themselves. Just as Jesus had while He walked the earth!

• ACTS 5:12–16:
  (vs.16) And also a multitude came from the cities around Jerusalem, bringing sick ones, and those being tormented by unclean spirits, who were all healed.

Again, we see here that it was the believers acting in faith who exercised their authority to heal and cast out demons. It is approached here as if this was the normal practice. Signs and wonders were done in every city as the Gospel was carried to them—by the hands of the apostles, and by the hands of the believers.

• EPHESIANS 6:12:
  For we do not wrestle against flesh and blood, but against principalities, against powers, against the world's rulers, of the darkness of this age, against spiritual wickedness in high places.

This is the answer to the original question (I just took a long time to get here). WE, the believers—Christians—the Saved do not fight in this realm. Our fight against wickedness is in the realm of the spirit. This is a higher level of authority. Neither do we wait for GOD to send deliverance, as they did in the OT—we speak our authority against the forces of darkness and establish His desire in the earth.

We have the power and the authority to wage war against the forces that influence the evil we face here on earth. Because of the Name of Jesus, we have an ability that is greater than that of Satan and all his demons. Old Testament saints did not have this. Philippians 2:9–10 tells us that GOD has given Him a Name that is above all names. And it is in that Name that we have our authority. We pray in that Name—we worship in that Name—we preach in that Name—we declare our authority in that Name.

I trust this has helped in your study of the Word of GOD. May you be blessed as you pursue all that GOD has for you in life and in ministry.

Geof W. Jackson, read bio
Director of the Grace School of Ministry/Director of Pastoral Care