The Saviour had visited the church in Smyrna and observed their situation. He mentions three aspects of their circumstances. First, they are experiencing persecution for their faith. Their experience is different from the church in Ephesus, even although it was close by. Second, he knows that persecution has been costly for them because it has made them poor (the word translated poverty was used of beggars). Probably they have lost their possessions. Third, the persecution seems to have been initiated by the Jews, who have slandered the Christians before the civil authorities. This was a common experience for the first-century church.
Yet things are not what they seem to be and Jesus points out two such details. First, the Christians in Smyrna, although they have lost everything, are not poor. Instead they are the richest people in Smyrna because their treasures are in heaven. The heavenly Banker assures them that he is protecting their investments, and these cannot be lost no matter what happens to them. In this regard, they were the opposite of the church of Laodicea.
Second, Jesus assures the Christians in Smyrna that they, and not the Jews, are the people of God. In contrast, the Jewish synagogue in Smyrna is actually the possession of Satan. This is very strong condemnation by the One who knows the hearts of men. Both the Christian community and the Jewish synagogue would have used the Old Testament: one of them had the light of God and saw Jesus in the scriptures, the other were blinded by the devil and opposed Jesus and his people. Jesus here says what Paul says elsewhere that a true Jew is one that is a Jew inwardly. The true circumcision are those who glory in Christ Jesus as they worship God (Phil. 3:3).
So Jesus assures his suffering people of their permanent identity and of their priceless investments.