When justice is done, it brings joy to the righteous but terror to evildoers.
It may be shocking to say but sometimes we as Christians get too caught up in love in mercy. Certainly God is a God of those things, but He is also a God of justice. God does not turn a blind eye to sin.
We must be careful to differentiate between justice and vengeance. We should never want to get back at someone because they hurt us in some way. We should not have such an attitude but we can rejoice when someone gets what they deserve.
Justice is a two way street. Sinners deserve punishment and they will not escape it in the end. But those who have been forgiven also deserve something. God blesses the righteous and we can be happy when they receive what they deserve as well. Although funerals are a sad time, it should also be a time of rejoicing for Christians who we know are now receiving their eternal reward.
Those who do wrong should be fearful of punishment. They should see others facing justice and should tremble and turn from their wicked ways. Sometimes it happens. Often people are sorry, but mainly because they got caught rather than because they did wrong.
We can rejoice in God’s justice because we know that it is perfect. It is never in revenge but is enacted out of holiness.