13 But we do not want you to be uninformed, brothers, about those who are asleep, that you may not grieve as others do who have no hope. 14 For since we believe that Jesus died and rose again, even so, through Jesus, God will bring with him those who have fallen asleep. 15 For this we declare to you by a word from the Lord, that we who are alive, who are left until the coming of the Lord, will not precede those who have fallen asleep. 16 For the Lord himself will descend from heaven with a cry of command, with the voice of an archangel, and with the sound of the trumpet of God. And the dead in Christ will rise first. 17 Then we who are alive, who are left, will be caught up together with them in the clouds to meet the Lord in the air, and so we will always be with the Lord. 18 Therefore encourage one another with these words.1 Thessalonians 4:13-18
The Greek in verse 13 conveys that Christians should not grieve. 😳 Often, that passage is read to mean that the way Christians grieve is different. There are different types of grief. Regardless, our grieving does look different because of our hope in Jesus.
In verse 17, the concern is not that they would not be together, but whether they will see Christ. Real grieving is for someone who might not have known Jesus.