Most people find it difficult to give comforting words for those who mourn, because they don't know the right words to use but proverbs 14:10 says that the tongue of the wise is healing. If you find it difficult to say comforting words it may be easier to go with group of people who can comfort,send a card, an e-mail, a text message, or a letter. you could simply mention a special quality that you remember about the person who died or share a happy memory you remember.
BELOW ARE SOME SOOTHING WORDS YOU CAN USE:
1: We don't know what to say except that we love you. we can't understand exactly how you feel, but Jehovah does and will keep raising you up. we hope that our prayers will help a little.
2: May Jehovah sustain you at this time of such great loss
3: May you find comfort in knowing that your dear one is safe in the memory of God, who will remember every details about him and bring him back again.
4: Your loved one will never have to face the last enemy, death ever again. in the meantime, his acts of faith live on until he stands up alive and whole in the paradise
5: While words fail to capture the pain of losing a loved one, we look forward to the time when words will fail to capture the joy of having our heavenly father return your dear one to you.