A beautiful love letter is found in the Gospel of John. Chapters 13-17 describes what Jesus wanted to share with his diciples, knowing it would be His last supper with them. I've picked up a few sentences, that convey His love to his diciples ... both then, now and in the future.
My Father’s house has many rooms; if that were not so, would I have told you that I am going there to prepare a place for you?
As the Father has loved me, so have I loved you. Now remain in my love. If you keep my commands, you will remain in my love, just as I have kept my Father’s commands and remain in his love. I have told you this so that my joy may be in you and that your joy may be complete. My command is this: Love each other as I have loved you. Greater love has no one than this: to lay down one’s life for one’s friends. You are my friends if you do what I command. Gospel of John 15:9-14
I have told you these things, so that in me you may have peace. In this world you will have trouble. But take heart! I have overcome the world. Gospel of John 16:33
... Let's remain in His love.