ĽJesusŐ disciples would not have much to go on here.
–The OT is explicit about the
existence of Satan and evil supernatural powers, and connects them with
idolatry & false religion.
–The OT also indicates Satan is
capable of miraculous activity, as were the magicians of Pharaoh in
Exodus.
–Otherwise, the main OT background
would be the evil spirit that comes on Saul and the lying spirit that
misleads AhabŐs false prophets.