So where does it come from then?
How does anyone make a free will, uncoerced, decision? All sin comes from the desires of the person...
Berean Standard Bible
James 1:14 But each one is tempted when by his own evil desires he is lured away and enticed.
This tells us that when Satan decided to rebel against GOD, that he thought about YHWH's proclamation of deity and HIS gospel of salvation,
Col 1:23, and didn't like something about it. If interpretations of other verses are true, the proclamation tweaked his pride. Since I cannot fathom that he thought he was equal to a proven deity, I suspect that he thought that YHWH was lying about being the only One True Living GOD, that HE was no better than anyone else which also meant that there was no such thing as sin, no hell, and no heavenly marriage.
He talked this up so much he actual got a rebellion going in heaven against YHWH and HIS gospel from people who also decided to accept, to believe, his interpretation of YHWH's proclamation...unwilling to accept that they were creations of a real GOD with a real purpose for HIS creation because they put their faith, their unproven hope, in the idea that HE was no better than anyone else and therefore a false god and therefore a sinner himself and as the first sinner, YHWH was the most evil sinner in the world.
This is still echoed in what pagans and Satanists say about YHWH, a common theme in the Satanic circles which I have studied.