Jude 1:6    And the angels which kept not their first estate, but left their own habitation, He hath reserved in everlasting chains under darkness unto the judgment of the great day.

 

     Here's why we came here in Jude. So these 'fallen angels’ or 'sons of God' as they are called in Gen.6:2, left their 'original state' or hierarchy of order in God's creation. This may have something to do with just how they were able to impregnate flesh woman as written in Gen.6.
     Many have a hard time understanding just what an 'angel' is. The word 'angel' simply means 'a messenger' ('aggello' in the Greek, Strong's no. 32). So angels are just 'sons of God', as also we who accept Christ now are called 'sons of God’.

 

John 1:12: But as many as received him, to them gave he power to become the sons of God, even to them that believe on his name.

 

Romans 8:14: For as many as are led by the Spirit of God, they are the sons of God.

 

Philippians 2:15: That ye may be blameless and harmless, the sons of God, without rebuke, in the midst of a crooked and perverse nation, among whom ye shine as lights in the world.

 

1 John: 1 He describeth the person of Christ, in whom we have eternal life, by a communion with God: 5 to which we must adjoin holiness of life, to testify the truth of that our communion and profession of faith, as also to assure us of the forgiveness of our sins by Christ’s death.

 

The difference being, we are in the flesh body with our spiritual body inside; the angels are in the spiritual body with no flesh. We will be in that same angelic state when we cast off our flesh also, revealing the spiritual body.

 

Paul I Cor.15: 3 By Christ’s resurrection, 12 he proveth the necessity of our resurrection, against all such as deny the resurrection of the body. 21The fruit, 35 and manner thereof, 51 and of the changing of them, that shall be found alive at the last day.

     Many think of angels as being similar to 'zoan’ or the special spirit beings God created to surround and protect His Throne (see Ezekiel). When Christ was asked about a woman who had seven husbands in the flesh, and when she dies, which one of her dead husbands would she be married to in heaven, Jesus replied, "For in the resurrection they neither marry, nor are given in marriage, but are as the angels of God in heaven."

 

 Matthew 22:30: For in the resurrection they neither marry, nor are given in marriage, but are as the angels of God in heaven.

 

 Rev.19:10 And I fell at his feet to worship him. And he said unto me, See thou do it not: I am thy fellowservant, and of thy brethren that have the testimony of Jesus: worship God: for the testimony of Jesus is the spirit of prophecy.

 

John bowed down to worship an angel about to give him a message, and the angel said not to do it (bow), for he was a "...fellow servant, and of thy brethren that have the testimony of Jesus...". That particular angel speaking to John had once been born flesh, through woman's womb, just like us, and then had cast the flesh off during death upon this earth.

 

 See Ecclesiastes 12: 1 joyful thanksgiving of the faithful for the mercies of God.