Angels
Angels are powerful beings. They are much stronger and more powerful than humans are.
Bless the LORD, you His angels, who excel in strength, who do His word, heeding the voice of His word. (Psalm 103:20)
9 then the Lord knows how to deliver the godly out of temptations and to reserve the unjust under punishment for the day of judgment, 10 and especially those who walk according to the flesh in the lust of uncleanness and despise authority. They are presumptuous, self-willed. They are not afraid to speak evil of dignitaries, 11 whereas angels, who are greater in power and might, do not bring a reviling accusation against them before the Lord. (2 Pet. 2:9-11)
One angel was able to roll away the stone covering the entrance to the tomb where Jesus was laid after His crucifixion. It appears his coming caused a great earthquake.
2 And behold, there was a great earthquake; for an angel of the Lord descended from heaven, and came and rolled back the stone from the door, and sat on it. (Matt. 28:2)
An angel of the Lord freed Peter and the Apostles when they were in prison. He told them to continue to preach the word of life.
17 Then the high priest rose up, and all those who were with him (which is the sect of the Sadducees), and they were filled with indignation, 18 and laid their hands on the apostles and put them in the common prison. 19 But at night an angel of the Lord opened the prison doors and brought them out, and said, 20 “Go, stand in the temple and speak to the people all the words of this life.” (Acts 5:17-20)
In the following instance, God sent just one angel to destroy the city of Jerusalem:
14 So the LORD sent a plague upon Israel, and seventy thousand men of Israel fell. 15 And God sent an angel to Jerusalem to destroy it. As he was destroying, the LORD looked and relented of the disaster, and said to the angel who was destroying, “It is enough; now restrain your hand.” (1 Chron. 21:14-15)
God sent two angels to warn Lot and his family to leave Sodom because the angels were going to destroy Sodom and Gomorrah due to the sexual perversion and immorality of their people. These cities were destroyed by fire and brimstone coming down from the heavens.
Now the two angels came to Sodom in the evening, and Lot was sitting in the gate of Sodom. When Lot saw them, he rose to meet them, and he bowed himself with his face toward the ground. 2 And he said, “Here now, my lords, please turn in to your servant’s house and spend the night, and wash your feet; then you may rise early and go on your way.” (Gen. 19:1, 2)
12 Then the men said to Lot, “Have you anyone else here? Son-in-law, your sons, your daughters, and whomever you have in the city—take them out of this place! 13 For we will destroy this place, because the outcry against them has grown great before the face of the LORD, and the LORD has sent us to destroy it.” (Gen. 19:12, 13)
24 Then the LORD rained brimstone and fire on Sodom and Gomorrah, from the LORD out of the heavens. 25 So He overthrew those cities, all the plain, all the inhabitants of the cities, and what grew on the ground. (Gen. 19:24, 25)
When Israel was held by Egypt in bondage and slavery, God sent a destroyer or death angel to kill the first born of every house that did not have the blood of the lamb on its door posts. For houses that did, the death angel passed over and the inhabitants were safe. This was a picture of the shedding of blood in the crucifixion of Jesus Christ, the Lamb of God and how His blood protects Christians from spiritual death in the lake of fire. In a sense, the death angel passes over us because we have the blood of Christ applied spiritually to the door posts of our hearts.
21 Then Moses called for all the elders of Israel and said to them, “Pick out and take lambs for yourselves according to your families, and kill the Passover lamb. 22 And you shall take a bunch of hyssop, dip it in the blood that is in the basin, and strike the lintel and the two doorposts with the blood that is in the basin. And none of you shall go out of the door of his house until morning. 23 For the LORD will pass through to strike the Egyptians; and when He sees the blood on the lintel and on the two doorposts, the LORD will pass over the door and not allow the destroyer to come into your houses to strike you. (Ex. 12:21-23)
Angels, as messengers of God, can move from heaven to earth immediately, in less than a split second. They are not limited by the dimensions of time and space as we are. Their speed in flight (as we think of it) often gives rise to the thought they have wings. There are many verses in the book of Revelation that give testimony to the great power of angels.
Demons
Devils or demons have great power to do signs and miracles to deceive and to commit evil against mankind.
9 So the great dragon was cast out, that serpent of old, called the Devil and Satan, who deceives the whole world; he was cast to the earth, and his angels were cast out with him. (Rev. 12:9)
The beast and the false prophet, who are agents of Satan (the dragon), are given great power to deceive many.
12 Then the sixth angel poured out his bowl on the great river Euphrates, and its water was dried up, so that the way of the kings from the east might be prepared. 13 And I saw three unclean spirits like frogs coming out of the mouth of the dragon, out of the mouth of the beast, and out of the mouth of the false prophet. 14 For they are spirits of demons, performing signs, which go out to the kings of the earth and of the whole world, to gather them to the battle of that great day of God Almighty. (Rev. 16:12-14)
19 And I saw the beast, the kings of the earth, and their armies, gathered together to make war against Him who sat on the horse and against His army. 20 Then the beast was captured, and with him the false prophet who worked signs in his presence, by which he deceived those who received the mark of the beast and those who worshiped his image. (Rev. 19:19-20)
The following verses show how powerful and evil Satan is. He is the prince of the power of the air who deceives mankind to sin against God, themselves, and others.
And you He made alive, who were dead in trespasses and sins, 2 in which you once walked according to the course of this world, according to the prince of the power of the air, the spirit who now works in the sons of disobedience, 3 among whom also we all once conducted ourselves in the lusts of our flesh, fulfilling the desires of the flesh and of the mind, and were by nature children of wrath, just as the others. (Eph. 2:1-3)
Our battle is not just within ourselves because of our sin nature, but it consists even more against Satan and the demons who rule the airways who are invisible to us. If our eyes were open to be able to see the demonic world around us, we would be shocked and terrified. We are in a war against demonic oppression. We must take on the whole armor of God to defeat the enemy. We must recognize that demons exist so that we can be serious about fighting them.
10 Finally, my brethren, be strong in the Lord and in the power of His might. 11 Put on the whole armor of God that you may be able to stand against the wiles of the devil. 12 For we do not wrestle against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this age, against spiritual hosts of wickedness in the heavenly places. 13 Therefore take up the whole armor of God that you may be able to withstand in the evil day, and having done all, to stand. (Eph. 6:10-13)