In the letter to the second church, Jesus reminds them that this letter is from the eternal God. He was there in the beginning, so he know what the world was supposed to be like. He will be there at the end, so he already knows how the story will end. And he has already experienced death; and he has already experienced a resurrection from the dead. This is something we are all going to experience. He has gone ahead of us, this time to assure us it's going to be OK.
And that's important to this church especially. They are not in a good place. First, they are poor. We all realize life is hard when people have insufficient resources to cope. And there is a lot of research about how poverty affect people: physically, psychologically, socially, emotionally and spiritually. People get beaten in all these areas. But also, the society at large was against them, because they choose to follow Jesus. Society was following the ways of the enemy, excluding God's family from community resources, sending them to prison -- increasing the difficulty of life on the family -- and even killing some.
Jesus does not warn this church about any wrong doing. And he praises them for being true and faithful in the midst of their oppressive circumstances. He reminds them of all the good things they will have, because they have a relationship with him. He encourages them to persevere, because they will share in the reward of real life -- life as they are designed to live. And they will share in the reward of an eternal relationship with him.