About the mark of the beast, it is in Genesis 4:15. If the beast is Satan, which is the general conclusion among believers, according to John 8:44, Jesus says Ye are of your father the devil, and the lusts of your father ye will do. He was a murderer from the beginning, and abode not in the truth, because there is no truth in him. When he speaketh a lie, he speaketh of his own: for he is a liar, and the father of it.
Now, this is not to say Cain is the beast nor is he Satan. But he was the first murderer and also the first liar.
Romans 8:8 11 But if the Spirit of him that raised up Jesus from the dead dwell in you, he that raised up Christ from the dead shall also quicken your mortal bodies by his Spirit that dwelleth in you.
The whole 8th chapter of Romans, but I didn't want to take up too much space.
In regard to no one will remain lost: Matthew 18:11, Luke 15:4, 15:6, 15:9, 15:32, 19:10, John 17:12.
Luke 6:35-36 But love ye your enemies, and do good, and lend, hoping for nothing again; and your reward shall be great, and ye shall be the children of the Highest: for he is kind unto the unthankful and to the evil.
Be ye therefore merciful, as your Father also is merciful.
The first couple of chapters of Hebrews contain information about Angels.
Angels are made from God, what is from God is eternal, no matter where it's found. Evil is from Satan, and it is subject to death, regardless of where it's found.
There is not really any way to cite specific scriptures on these things, because the whole bible contains this information, but unless you are familiar with it as a whole, it's hard to correlate things with each other, and it takes years of reading to make many associations, there is just a lot in there. Every time I read it, I find more and more meaning is revealed to me. In fact, there could be no more perfect an arrangement and presentation of knowledge than what is found in its pages. I say this having been baptized for 27 years, and never have I taken a break from seeking the Truth by way of the Holy Spirit through reading the bible.
The part which says 'It is my personal opinion that, with eternity being so long , this current episode of humanity is just one chapter, and the chapters go on and on until all are back to their Creator. ' I clarified as being of my own opinion, which, actually isn't just merely an opinion, but that's the best way to state it, for several reasons. It isn't however, a result of twisting or contorting scripture. It's from another source, just as trustworthy.
John 7:38 He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water.
John 4:24 God is a Spirit: and they that worship him must worship him in spirit and in truth.
John 8:32 And ye shall know the truth, and the truth shall make you free.
John 14:17 Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you.
Romans 9:1 I say the truth in Christ, I lie not, my conscience also bearing me witness in the Holy Ghost
The promise of God is life. God makes no threats nor does he put fear in the heart of man. The fear that man feels is the discord of the flesh and the spirit. The flesh feels fear but the soul is quickened by faith, by which the Spirit is given and fear is then relieved.
The threat of a fiery death in eternal anguish does not come from a merciful and kind Father, and Jesus says the Father is merciful. How many lost sheep are turned away from the fold by the man who declares fire and brimstone for everyone who's not doing as he is? Grandma always said you catch more flies with honey than vinegar, and in this case it's the honey that is the truth of the Son of Man and the vinegar that is the falseness, borne of man's poison.