After Ephesus, Smyrna would be the next destination that the courier delivering the message of Revelation to the seven churches in Asia Minor would visit in his travels. So, Jesus addresses the church at Smyrna immediately after speaking to the church at Ephesus, as we see in Revelation 2:8–11.
During the first century, Smyrna was an important locale for worship of the Roman emperor, which helps explain what Jesus says to the church at Smyrna. Revelation 2:9 refers to “the slander of those who say that they are Jews and are not, but are a synagogue of Satan.” Most people in the Roman Empire were compelled to worship the emperor at various points in the history of caesar worship, but Jews were granted an exception. Initially, the early Christians benefited from this exception, for the Romans saw Christianity as a sect of Judaism. In time, however, especially after the Christians did not join the Jews in rebelling against Rome in AD 70, Jews and Christians became strongly differentiated. In some places, the Jews informed Roman authorities on Christians who did not worship the emperor. This seems to be what happened to Polycarp, the second-century bishop of Smyrna, who went to his death for worshiping only Christ. The Jews in Smyrna slandered the original audience of Revelation by exposing the refusal of Christians in that city to worship the caesar.
Naturally, this would have inspired the Christians in Smyrna to fear for their lives. Recognizing this, Jesus tells this church not to fear the ten-day imprisonment and martyrdom that some of them were about to face. Notably, Smyrna and Philadelphia are the only churches of the seven that are not issued a call to repent. Jesus gives only an encouragement to persevere, promising the crown of life and freedom from the second death to those who refuse to deny Him even when it means their deaths (vv. 10–11). Later in the book of Revelation, we learn that the second death is the eternal judgment that awaits all whose names are not written in the Book of Life (20:14–15). The promise to those who conquer—to those who have true, persevering faith in Jesus—is eternal life (2:11).
Today, we are called to the same persevering faith. Even if we never face martyrdom, we may be slandered for our witness to Christ. We might lose our jobs, be called names, or be disrespected by our families. Regardless, we will reign with Christ (2 Tim. 2:12).