7.1) Gospels and Acts
To begin with, we deduce from the Gospels that “Satan” and “Devil” are synonymous, so we can simply refer to Satan as “Satan.”
We have seen that in the Book of Job, Satan is one of the Angels of God who patrols the Earth and reports on the activities of human beings. In consultation with God, he proposes tests to determine their virtue and fidelity (1.2). He also files reports of human wrongdoing in the Heavenly Court. This is evident both in Job and in Zechariah, where he builds a case against Jesus (Joshua) the High Priest (1.3).
In the case of Job, Satan’s surmise about the frailty of his virtue proves to be unwarranted, and he is chided for overzealous prosecution. In Zechariah, Jesus the High Priest is absolved of whatever faults are to be found in him, and Satan is rebuked for insisting upon them.
Opening up the New Testament, we see right away in the Gospel of Matthew, that Satan appears on earth to exercise his testing function with Jesus, taking him through a series of three explicit trials. Not surprisingly, Jesus easily emerges a paragon of right intention and right action (4.2).
The Gospel of Luke shows Satan conducting the same three tests, presumably aimed at establishing what kind of a Messiah Jesus will be. Here Satan asserts that he has been appointed to rule over the kingdoms of the World. Jesus accepts this claim as true, but points out to his Disciples that, because of their activity, Satan’s power will come to an end (he will fall “like lightning”). However, our last view of Satan in Luke’s Gospel shows him still at work testing Jesus, having suborned Judas to set the Passion underway. We also see him still consulting (with God) about other tests: he receives permission to test the Apostles. Peter will fail his test, but at Jesus’s intercession he will recover himself and be in a position to strengthen his brethren in their trials (4.3).
John’s Gospel confirms that Satan is the Ruler of the World, and that his rule will soon come to an end, but nevertheless he will still be active in the future, after Jesus has departed to the Father. Jesus also implicates Satan in provoking sinfulness from earliest times, beginning with the first murder, Cain’s killing of his brother (4.4). John’s First Epistle confirms this point (6.3).
In Luke’s Acts of the Apostles, we see that Satan continues to operate, filling the hearts of sinners (4.3).