"But why are we concerned with Satan in this case? My point was that every time humans reject God they commit evil"
I believe you said "Humans are authors of evil". The author of evil, if you can say that, was Lucifer/Satan. He was the tempter who caused Adam and Eve to sin and brought ruin to mankind. After the fall mankind could only sin until the Redeemer came.
Humans can say "no" to evil, but they don't. In doing that, they re-invent evil every time. Satan may have started it, but evil is rendered powerless unless we give in to it.
Actually, God in His mercy gave Adam every opportunity to repent and ask for forgiveness. The real sin of Adam is not that he and Eve were foled by the cunning Serpent, but that Adam blamed God for his sin. He could have repented but he chose not to.
Did he tempt Adam and Eve? Yes. Did they choose to sin? Yes.