The Accusers: Psalm 109:29

Colossians 2:
13 And you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him, having forgiven us all our trespasses,14 by canceling the record of debt that stood against us with its legal demands. This he set aside, nailing it to the cross. 15 He disarmed the rulers and authorities and put them to open shame, by triumphing over them in him. 16 Therefore let no one pass judgment on you in questions of food and drink, or with regard to a festival or a new moon or a Sabbath. 17 These are a shadow of the things to come, but the substance belongs toChrist.18 Let no one disqualify you, insisting on asceticism and worship of angels, going on in detail about visions, puffed up without reason by his sensuous mind, (Habakkuk2:4) 19 and not holding fast to the Head, from whom the whole body, nourished and knit together through its joints and ligaments, grows with a growth that is from God. 20 If with Christ you died to the elemental spirits of the world, why, as if you were still alive in the world, do you submit to regulations—21 "Do not handle, Do not taste, Do not touch" 22 (referring to things that all perish as they are used)—according to human precepts and teachings? 

 The rulers and authorities of which Paul speaks of in THIS CONTEXT, are the neo-pharisees, i.e. the purveyors of legalism, the holiness brigade, those who preach a progressive sanctification, do all the right things or else, sinless perfection or bust; “church leadership” and their followers.Even those who claim “heavenly visions” demand an allegiance to their “revelation”.                                                                                                                      
Paul says they are "disarmed" by Christ. For those of us in Christ (the saints, those whom He has sanctified)there is no legal requirement that can be brought to bear against us. Christ accomplished it all and satisfies the righteous requirement of the law on our behalf. Christ has died, He has risen and has ascended to the right hand of the Father. Satan has been cast down. The enemy no longer stands before the throne as accuser of the brothers. (Rev 12:1-11; Job 1:6-12; the truth be told, Satan would no longer have to, as there are many who call themselves brothers who now do the job for him, and quite well I might add).
Paul spent a great amount of time in his calling as an apostle battling these types.
Christ, through His death and resurrection, disarmed them. They have no effective weapon to use against us who stand before the Lord in and through Christ (John 8:3-11).

 Isaiah 54:  (Isaiah also saw His day and rejoiced. John8:56-58) 
14 In righteousness you shall be established; you shall be far from oppression, for you shall not fear; and from terror, for it shall not come near you. 15 If anyone stirs up strife, it is not from me; whoever stirs up strife with you shall fall because of you.
(1 Timothy 1:1-11; Romans 14; all of the letter to the Galatians)

 16 Behold, I have created the smith who blows the fire of coals and produces a weapon for its purpose. I have also created the ravager to destroy;
(God is sovereign. He is creator of both weapon, and the makers of weaponry. He determines the purpose of both. All things serve Him; therefore………)

 17 no weapon that is fashioned against you shall succeed, and you shall refute every tongue that rises against you in judgment. This is the heritage of the servants of the LORD and their vindication from me, declares the LORD."
(So, He has purposed that those whom the Son has set free, are free indeed! John 8:34-36; Romans 6:11-18)

Galatians 2:4 Yet because of false brothers secretly brought in—who slipped in to spy out our freedom that we have in Christ Jesus, so that they might bring us into slavery—5 to them we did not yield in submission even for a moment, so that the truth of the gospel might be preserved for you. 

Anyone coming to you with the “gospel” of righteousness and sanctification, accomplished through our dead works, i.e. our freewill choices, (the trappings of our religious rituals and settings), as necessary additions to the Lord’s finished work is not bringing you “the good news” at all.
Solus Christus
Soli Deo Gloria