At the time(year) this was written who or what rose or will rise from the pit/abyss?
The Angels who came down to earth in Genisis 3 and had relationships with woman.. They left their first estate ( heaven) and sinned and for that they where bound up in the bottomless pit waiting for the day of the LORD when they will be released for a short time and play a part in the wrath being poured out upon the earth..
Jude 1: KJV
"{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. {7} Even as Sodom and Gomorrha, and the cities about them in like manner,
giving themselves over to fornication, and going after strange flesh, are set forth for an example, suffering the vengeance of eternal fire."
Genesis 6: KJV
1 "And it came to pass, when men began to multiply on the face of the earth, and daughters were born unto them, {2}
That the sons of God saw the daughters of men that they were fair; and they took them wives of all which they chose. {3} And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years. {4}
There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown."
Sons of God are Angels
Job 1: KJV
6 "¶ Now there was a day when
the sons of God came to present themselves before the LORD,
and Satan came also among them. {7} And the LORD said unto Satan, Whence comest thou? Then Satan answered the LORD, and said, From going to and fro in the earth, and from walking up and down in it. {8} And the LORD said unto Satan, Hast thou considered my servant Job, that there is none like him in the earth, a perfect and an upright man, one that feareth God, and escheweth evil?"