The outworking of the victory of Christ “was” and “still is” bringing the devil to nought. We must keep in mind that it’s after the cross that we read:
Hebrews 2:8
“…You have put all things in subjection under his feet.” For in that He put all in subjection under him, He left nothing that is not put under him. But now we do not yet see all things put under him.
Romans 16:20
The God of peace will soon crush Satan under your feet. The grace of our Lord Jesus be with you.….
“Soon” is a relative term, particularly when inspired by a God for whom ‘a thousand years are as one day.’ 2 Peter 3:8.
The devil is still running around causing death and mayhem—not simply the fear of death and mayhem.
Satan still tempts (1 Thes. 3:5), prowls (1 Peter 5:8), fills people’s hearts to lie (Acts 5:3), hinders ministry travel (1 Thes. 2:18), is considered ‘the god of this age,’ and blinds people’s minds (2 Cor. 4:4), masquerades as a good angel (2 Cor. 11:14), develops plans against us (Eph. 6:11), and deceives and leads people away from devotion to Christ (2 Cor. 11:3).
And even after the return of Christ, Satan will be running around causing death and mayhem, including—as he did in Job 1:16, and as as he tempted the disciples to do in Luke 9:54-55—sending fire “of God” from heaven:
Revelation 20:7-10
7 Now when the thousand years have expired, Satan will be released from his prison 8 and will go out to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together to battle, whose number is as the sand of the sea. 9 They went up on the breadth of the earth and surrounded the camp of the saints and the beloved city. And fire came down from God out of heaven and devoured them. 10 The devil, who deceived them, was cast into the lake of fire and brimstone where the beast and the false prophet are. And they will be tormented day and night forever and ever [or, “to the ages of the ages.”]
(If this Revelation passage indeed speaks of a literal, killing fire, as in Job 1:16, and Luke 9:54-55, you might ask, why would Satan kill his faithful followers? But I would argue that the Egyptians in Exodus were his faithful followers too, and that he nevertheless killed them through the plagues. Satan is a killer, not God. John 10:10.)
We in the Church (figuratively a woman, the Bride) have our rôle in the ongoing, gradual outworking of the victory of Jesus—
Matthew 13:33
Another parable He spoke to them: “The kingdom of heaven is like leaven, which a woman took and hid in three measures of meal till it was all leavened.”
We are to fulfill our responsibility to assist in the leavening process, and thus not ‘neglect our so great a salvation.’ (Hebrews 2:3). And one day, critical mass will be reached, and the whole lump—Creation—will be completely permeated with love and immortality.
We are to submit to God, and resist the devil in our lives, and in our neighbors’ lives, so that he will flee from us (James 4:7)—and so our neighbors too can be free to draw near to God.