Answer:
Acts 10:42
And he commanded us to preach unto the people, and to testify that it is he which was ordained of God to be the Judge of quick and dead.
2 Ti 4:1
I charge thee therefore before God, and the Lord Jesus Christ, who shall judge the quick and the dead at his appearing and his kingdom;
It simply means that when Christ returns He will judge both the quick (living) and the dead. We will all give account and answer to whether or not we confessed and accepted Him as our Lord and Savior.