Lets start with Gnosticism
Gnostics think that there is the Monad, the one, the true God so to speak. From him comes Sophia the spirit and somewhere down the line Yaldabaoth. Yaldabaoth is the So called Demiurge that created this fake reality, depending on who you ask out of evilness or confusion and is the cause for our limitations and ultimately death and traps us in here through rebirth LARPing as the real God.
However now comes the hook up. While these seems like an obvious hint to Yaldabaoth being Satan, being the cause of death, the reason for our fall (entrapment in this reality) and ruling this world through lies, fear and temptation Gnostics now claim that the God of the OT is this Demiurge, and that Jesus is Lucifer is the Serpent in Eden send by the Monad/true God to free us from the Demiurge that wanted us dumb (forbidding the fruit of knowledge of good and evil) and oppressed us and was a tyrant with his "unnecessary" strict law. Its an effort to seperate the OT from the NT but Jesus himself says
>17Do not think that I have come to abolish the Law or the Prophets; I have not come to abolish them, but to fulfill them.
So why would Jesus, send by the real God want to fulfill the law and prophets of the OT send by the false God? Obviously this doesnt make sense and shows OT God and Jesus are on the same side, the serpent even gets identified in revelations as Satan
>2He seized the dragon, the ancient serpent who is the devil and Satan, and bound him for a thousand years.
Its an effort to get rid of the commandments and guidelines of the OT, watering down the traditions and ultimately make us fall from the right path by promising liberation much like SJW do. (Cant say often enough that Satan will come as a SJW promising freedom from Gods oppressive and useless laws)