Let's take a look at what scripture teaches on this.
In Luke we see the account of seventy disciples that Jesus had sent out to preach and cast out demons. They return with joy saying:
Luk 10:17 And the seventy returned again with joy, saying, Lord, even the devils are subject unto us through thy name.
Luk 10:18 And he said unto them, I beheld Satan as lightning fall from heaven.
Luk 10:19 Behold, I give unto you power to tread on serpents and scorpions, and over all the power of the enemy: and nothing shall by any means hurt you.
Luk 10:20 Notwithstanding in this rejoice not, that the spirits are subject unto you; but rather rejoice, because your names are written in heaven.
See also: Mar 16:18, Act 28:5, Rom 16:20
Notice that Jesus makes a point of making as astounding proclamation-
"I saw Satan fall from heaven". This reveals several things:
1. Jesus was present when Satan was cast out of heaven, he witnessed the event between the Father and Lucifer spoken of in Isaiah and Ezekiel. Is 14:12, Eze 28:12-19
2. We see this as evidence of his statements of coming from above, and of his position as a Son, in relation to the Father. John 10:30, John 17:22
3. His purpose is revealed, to destroy the works of the devil. 1Jn 3:8, see also- 1Jn_3:5; Gen_3:15; Isa_27:1; Mar_1:24; Luk_10:18; Joh_12:31, Joh_16:11; Rom_16:20; Col_2:15; Heb_2:14; Rev_20:2-3, Rev_20:10, Rev_20:15
You could spend weeks studying the significance of these verses, and come away with a grounded, sound faith in whom you believe; it would be well worth it. Your soul would find it nourishment and you would see your position with the Lord in a very different way. When you know who you are in Christ, great inner strength comes.
THE SOURCES OF DEEPEST JOY
"How triumphant the return of the evangelists! With faces flushed with pride and hearts high with elation, they returned to the Master with their reports. What wisdom it is to talk our work over with Jesus! Even the demons were subject to His Name. He was not surprised. While He had been watching, bearing them up by His intercessions, He had seen an alteration take place in the unseen world. Satan had fallen, as though the work done by these humble men had turned the scale against him. Is it not so still? What we do is of eternal importance.
Then, “in that same hour” it seemed as though the flood-gates of the Savior’s soul were flung open for very joy. He rejoiced that babe-like hearts might know the deep things of God; that all things were opened to Him in His humanity as in the ages before He became man; and that He was permitted to reveal the Father to those who loved and obeyed Him. It was for these, and for us, to know things hidden from prophets and kings."
However, though Jesus rejoices with them, he finishes with a caution we need- we are not to rejoice in our own power, give no occasion for pride-rejoice only in knowing we are God's children. Rejoice in that we are known in heaven, and it is our eternal destination.
In closing, the above study will bring us to the verses that I go to often, and remind myself when facing great adversity-
1Jn 5:4 For whatsoever is born of God overcometh the world: and this is the victory that overcometh the world, even our faith.
1Jn 5:5 Who is he that overcometh the world, but he that believeth that Jesus is the Son of God?
We are on the winning side, Jesus overcame this world, we will also, if we heed these scriptures and put them into practice in our daily lives.