Via Justin Taylor's blog Doug Moo's 140 word summary of Justification.
The Bible pictures all human beings as defendants in a courtroom: a courtroom in which God is the judge and our sins constitute the evidence against us. The judge weighs the evidence and finds every single one of us guilty of sin and announces that we, therefore, must be condemned. The marvellous news of justification is that God has himself provided for us the means of escaping that condemnation: by responding to his gracious initiative in faith, we become joined with Christ, who died for us and was raised for us. We become joined to Christ, who takes on himself the penalty for our sin and covers us with the ‘righteousness’ that we need to reverse the verdict of condemnation and receive the verdict of ‘justified’, ‘right’ with God. And because we have been joined to Christ, the holy one, and have in that union received the gift of God’s powerful holy Spirit, we, who have been justified, also find our lives transformed so that we love God and neighbour.