Revelation 2:18 And unto the angel of the church in Thyatira write; These things saith the Son of God, who hath his eyes like unto a flame of fire, and his feet are like fine brass;
Jesus identifies Himself to the church in Thyatira as “the Son of God, who hath His eyes like unto a flame of fire, and His feet are like fine brass.” This seems to emphasize His power and authority in judgment.
Revelation 2:19 I know thy works, and charity, and service, and faith, and thy patience, and thy works; and the last to be more than the first.
Again, God knows their works/deeds/actions/behavior, their charity (agape—love/goodwill), service/ministry, faith (moral conviction, fidelity to the truth), and patience (steadfastness, endurance). Then He repeats that He knows their works, to the point that He sees that they are doing much more now than in the beginning.
The above are all good things. But the Lord still has words of rebuke for them. Why?
Revelation 2:20 Notwithstanding I have a few things against thee, because thou sufferest that woman Jezebel, which calleth herself a prophetess, to teach and to seduce my servants to commit fornication, and to eat things sacrificed unto idols.
They (the church as a whole) suffer (don’t bother, allow, permit) that woman Jezebel, who calls herself a prophetess, to teach and seduce the believers to commit fornication and eat things sacrificed unto idols. Jezebel is a generic term for a false prophet/teacher; she claims to have special enlightenment.
This reminds me of the warning in Matthew 13:33—“Another parable spake he unto them; The kingdom of heaven is like unto leaven, which a woman took, and hid in three measures of meal, till the whole was leavened.”
False teachers in the church tend to emerge gradually. They introduce their false teachings in increments and before you know it, they have a group of followers in the church that have been deceived by their false teachings.
Eating things sacrificed to idols seems to be indicative of a willingness to compromise with the world instead of coming out from among them and being separate (cf 2Corinthians 6:17).
Revelation 2:21-22 And I gave her space to repent of her fornication; and she repented not. Behold, I will cast her into a bed, and them that commit adultery with her into great tribulation, except they repent of their deeds.
According to the wording given, it appears to me that there was a specific person, false teacher, at that point in time that was being permitted to operate in this church. God even states specifically that He had given her time to repent of her spiritual adultery, but she chose not to.
God warns that those who had chosen to consort with her in her immoral activity would experience great tribulation unless they repented (change of heart/mind/purpose).