“Everyone who commits sin is a slave to sin … So if the Son sets you free, you will be free indeed” (v34-36). Jesus spent his ministry telling people the truth: that we are slaves to sin (whether Jew or Gentile), and he was sent by God to set us free. However, we must first recognize our bondage, and people in Jesus day (like us) allowed pride, laziness, denial, fear, and idolatry (v13,33,39) to keep them from accepting his offer of freedom.
Knowing the truth is not an abstract idea, but rather knowing Jesus himself (v31-32). He breaks the powers that enslave us and gives us the right to live freely as God’s beloved children.