Jesus is not saying that God has a hit squad that takes out people who are sinners, and you could be next.  Jesus’ whole life is contrary to that.  What he seems to be saying is that, since we are all going to die, and since we are all sinners, the only way that our death won’t be a tragedy, is if we repent.  If we realize how broken we are, how great God is and what our life can become if lived through Him.  Jesus seems to be saying that a peaceful death may be tragic and a violent death may be triumph, it depends totally on whether or not we discovered to whom we belong to and what ultimately our life is for.