“Because angels are created as God’s obligate servants. It’s their nature. They were not given dominion over anything. To suggest that an angel rebels against being a servant to God is to say that a dog rebels against being a dog.”
“Where does it say that angels have free will?”
There are two classic prophecies that in their dual reference explain Satan’s fall and Peter’s and Jude’s statements concerning angelic sin.
Eze 28:11-19, “Moreover the word of the LORD came unto me, saying, Son of man, take up a lamentation upon the king of Tyrus, and say unto him, Thus saith the Lord GOD; Thou sealest up the sum, full of wisdom, and perfect in beauty. Thou hast been in Eden the garden of God; every precious stone [was] thy covering, the sardius, topaz, and the diamond, the beryl, the onyx, and the jasper, the sapphire, the emerald, and the carbuncle, and gold: the workmanship of thy tabrets and of thy pipes was prepared in thee in the day that thou wast created. Thou [art] the anointed cherub that covereth; and I have set thee [so]: thou wast upon the holy mountain of God; thou hast walked up and down in the midst of the stones of fire. Thou [wast] perfect in thy ways from the day that thou wast created, till iniquity was found in thee. You traded far and wide. You learned to be violent, and you sinned. So I threw you down from God’s mountain in disgrace. The guardian angel forced you out from the fiery stones. You became too proud because of your beauty. You wasted your wisdom because of your greatness. So I threw you to the ground and left you in front of the kings so that they could see you. You dishonored your own holy places because of your many sins and dishonest trade. So I set fire to you to burn you up. I turned you into ashes on the ground in the presence of all who saw you. All the nations who knew you are horrified because of you. You have come to a terrible end, and you will never exist again.’”
Isa 14:12-17, “How art thou fallen from heaven, O Lucifer, son of the morning! [how] art thou cut down to the ground, which didst weaken the nations! For thou hast said in thine heart, I will ascend into heaven, I will exalt my throne above the stars of God: I will sit also upon the mount of the congregation, in the sides of the north: I will ascend above the heights of the clouds; I will be like the most High. Yet thou shalt be brought down to hell, to the sides of the pit. They that see thee shall narrowly look upon thee, [and] consider thee, [saying, Is] this the man that made the earth to tremble, that did shake kingdoms; [That] made the world as a wilderness, and destroyed the cities thereof; [that] opened not the house of his prisoners?“
2Pe 2:4, “For if God spared not the angels that sinned, but cast [them] down to hell, and delivered [them] into chains of darkness, to be reserved unto judgment;”
Jud 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.”
“such as what was God ‘doing’ the entire eternity,”
God is timeless, unchangeable; the “Alpha and Omega”. What He is doing in the ever present is working all (Rom. 8:28) “things together for good to them that love God, to them who are the called according to [his] purpose and (Heb. 13:21) “working in you that which is well pleasing in his sight, through Jesus Christ”.
“why did he create the world if he didn’t lack anything, and is perfect?”
I explained that as best I could. His nature is love, best expressed in self-giving.
“And who is he trying to impress? etc.”
Paul seems to say it is all created beings; mankind and spirit beings.
Eph. 3:9-11, “And to make all men see what is the fellowship of the mystery, which from the beginning of the world hath been hid in God, who created all things by Jesus Christ: To the intent that now unto the principalities and powers in heavenly places might be known by the church the manifold wisdom of God, According to the eternal purpose which he purposed in Christ Jesus our Lord:“
2 Pet and Jude state that angels sinned but they give no source, which might be "apocryphal."
22For I will rise up against them, saith the LORD of hosts, and cut off from Babylon the name, and remnant, and son, and nephew, saith the LORD.and then 25
25That I will break the Assyrian in my land, and upon my mountains tread him under foot: then shall his yoke depart from off them, and his burden depart from off their shoulders.This " For thou hast said in thine heart, I will ascend into heaven, I will exalt my throne above the stars of God: I will sit also upon the mount of the congregation, in the sides of the north: I will ascend above the heights of the clouds; I will be like the most High" is what the king of Babylon (Nebuchadnessar and descendents) thought of themselves.
That is a perfect sentence.