Helpful words by John Piper from his blog post “Death: Shall We Weep or Rejoice?“:
What should we conclude from this?
We should conclude that our sorrows at the death of a believer are joyful sorrows, and our rejoicing at the death of a believer is a sorrowful rejoicing. There is nothing hopeless about the sorrow. And there is nothing flippant about the joy. The joy hurts. And the sorrow is softened with invincible hope.