Good point!
Devil, from diabolos, "slanderer".
Satan, "adversary".
Like when Jesus said to Peter, Get thee behind me, Satan! He may have been saying that Peter was being his adversary, rather than actually calling him Satan, as in, the devil. Still it would have left a sting!
Much love!
The point is that we are all of Satan or under such a influence due to the Stain of original Sin, Jesus had not risen yet, so Peter tho he had faith in Jesus but did not truly know who Jesus truly was in fact, until Jesus went to Heaven.
The same is with a water baptised they have faith in Jesus but they do not know Jesus truly, until they become truly born again.
If one is not for Christ Jesus, then they are in the sewer with Satan.
The works of the Devil is a diabolical slanderer.
Devil is commonly applied to them angels who with Satan, rebelled against God.
A devil is an angel who by revolt against God has lost supernatural grace.
Lucifer is known as the Devil; the other devils, as demons.
Lucifer leads the rebelling angels, the devils want to be like to God, so to rob him of his supremacy as their creator. they ensnare and persecute people.
Angels are messengers their can be good and also their is the bad ones.