I chose to stay pretty much off the BB and just lurk for a time. However there are a 'few' threads recently which I have engaged for my own reasons but this is one I will do so only because there is a scripture that hasn't been brought up that speaks to this issue - IMO.
WHile it deals with men it's application is universal to both men AND angels to a point and may shed some light on this.
Hebrews 6
Hbr 6:4 For [it is] impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,
Hbr 6:5 And have tasted the good word of God, and the powers of the world to come,
Hbr 6:6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put [him] to an open shame.
Note first: It is
impossible for those who (have come to know and partake)...if they fall away,
to renew them again.
This same principle of falling away thereby sealing them in condemnation can be applied to the Angelic Host with one difference.
We (as men) have to come to know these things because we are alienated from God and Life, and for THAT reason we CAN BE redeemed.
Angels ALREADY ARE in the presense of God, seeing God in all His glory and slendor, KNOWING already the truth of His Word and The Truth, His Word - Jesus.
They are already 'partakers' so to speak, and therefore if they should fall it is impossible to renew them.
How is Adam different than Satan in this. Scripture states that Adam walked with God in the Evening only. It doesn't state that God revealed Himself completely to Adam nor that Adam partook in ANY of the spiritual blessing that Christ redeemed men do. With maybe the exception of learning about God and being able to speak with God. However, these were and are a natural means wereby men gather and obtain information to aquire knowlegde and understanding which are, interestingly enough, filtered through our nature. Adams nature was not corrupted yet with sin so he COULD grow spritually in knowledge and understanding of God in the natural man unlike us. Our nature is contrary to God and all information we recieve through natural means are twisted becuase of our twisted nature away from God. And it is for that reason we can not KNOW God nor will we desire to, unless God bypass the natural man and spiritually reveal truth directly to us - but that is somewhat a different issue)
Adam was not enlightened to the knowledge of God as such, and did not taste the heavenly gift, and was not made a partaker of the Holy Ghost, and had not tasted the good word of God, and the powers of the world to come. Therefore Adam COULD BE redeemed.
But Satan on the other hand. Was in the very presense of God, ministered before Him, saw the fulness of His glory, KNEW His Word and Power of God. He knew the truth and rejected it. So for him there is no redeption. He saw it all (no need for faith) and rejected it.
But that is my two cents.