Paul writes in 1 Thessalonians 4:13, "Brothers, we do not want you to be ignorant about those who fall asleep, or to grieve like the rest of men, who have no hope."
Paul is not saying that since you have hope you won't grieve. He's not suggesting you should be somewhere between hope and grief. He's suggesting an extreme balance. He's saying, "I want you to grieve, but not hopelessly. I want you to have hopeful grief."
First, he says, Christians grieve. The Bible doesn't suggest to us a stoic approach to death. The most remarkable example of grief in the face of death is Jesus Himself at the tomb of Lazarus. Jesus didn't at all take the Victorian approach of keeping a stiff upper lip.....
.....Here is the balance Paul is suggesting - take your anger and grief and rub hope into it, the way people used to rub salt into meat to keep it from going bad. Rub hope deep into your grief and it will make you wise.
- Tim Keller in the book O Love That Will Not Let Me Go, edited by Nancy Guthrie (pages 87-88)