What Is the Synagogue of Satan?

Revelation 2:8-11 (MEV) “To the angel of the church in Smyrna write:
“The First and the Last, who was dead and came to life, says these things: 9 I know your works and tribulation and poverty (but you are rich). And I know the blasphemy of those who say they are Jews and are not, but are a synagogue of Satan. 10 Do not fear any of those things which you are about to suffer. Look, the devil is about to throw some of you into prison, that you may be tried, and you will have tribulation for ten days. Be faithful unto death, and I will give you the crown of life. 11 “He who has an ear, let him hear what the Spirit says to the churches. He who overcomes shall not be hurt by the second death.
The first and the last is a title of the Lord Jesus Christ. It is an idiom referring to the completeness, perfection, and sovereignty of Jesus Christ. In every area, situation, trait, action, plans, leadership, Highly Priestly ministry, etc., Jesus is the ultimate, the greatest, beyond which is impossible to improve. Jesus is also the firstborn with all the extra blessings regarding leadership, riches, and honor.
The dead and came to life refers to His death on the Cross and resurrection. All die sometime, except at the end of the age, but the death of Jesus is a ministry of substitutionary atonement as the Passover Over lamb (John 1:29 and 1 Corinthians 5:7). Jesus is also the first human to have a permanent resurrection. All other resurrections resulted in natural death later.
Jesus knows everything about the church in Smyrna (modern-day Izmir) and each individual. He knows our needs, hurts, thoughts, etc.
There is a synagogue in Smyrna that has members that are especially evil, do not serve the God of Abraham, Isaac, and Jacob. This synagogue, evidently, was particularly  persecutory towards the believers. Paul before his Damascus road conversion was of this mindset and action, too. The synagogue of Satan is not all, most, or part of ethnic Jews, the nation of Israel, or anything else. It is this particular synagogue. Compare Acts 13:50, Acts 17:5, and 1 Thessalonians 2:14-16.
They are motivated by satan as seen in verse 10. They act the same way some do today, namely, if they have a problem, they kill the person. This is unlawful. Lawful killing can be in war, self-defense, or government punishment.
Jesus finally encourages the believers. Jesus did not decree such evil activities as some theologies love to promote; He knew and knows the future. He also gives them a promise, “He who overcomes shall not be hurt by the second death.”
The synagogue of satan in the context of the passage is a particular synagogue in Smyrna who is very evil towards Jesus Christ and those who believe in Him. It does not refer to a rebellious church or a church that an individual doesn’t like, so the commentator is slinging a slander.
Jesus finally encourages the believers. Jesus did not decree such evil activities as some theologies love to promote; He knew and knows the future. He also gives them a promise, “He who overcomes shall not be hurt by the second death.”
The synagogue of satan in the context of the passage is a particular synagogue in Smyrna who is very evil towards Jesus Christ and those who believe in Him. It does not refer to rebellious church or a church that an individual doesn’t like, so the commentator is slinging a slander.