What it means

When you were dead in your trespasses and in the uncircumcision of your sinful nature, God made you alive with Christ. He forgave us all our trespasses, having canceled the debt ascribed to us in the decrees that stood against us. He took it away, nailing it to the cross! And having disarmed the powers and authorities, He made a public spectacle of them, triumphing over them by the cross.

From Colossians. Read the verses around it when you can.