Verse 18: And unto the angel of the church in Thyatira write; These things saith the Son of God, (Rev. 1:14, 15) who hath his eyes like unto a flame of fire, and his feet are like fine brass…
[To the Angel of Thyatira] This was not Carpus, but someone older than him. Now, Thyatira is a city attributed sometimes to Mysia, sometimes to Lydia (Grotius); the last city of the Mysians, a colony of the Macedonians (Menochius). From this heretics were contending that the Apocalypse was to be rejected, because there was at that time no Church in Thyatira (Ribera). Response: 1. Therefore, John here Prophetically predicts the future establishment of that Church (Epiphanius in Ribera). 2. There was a Church in that place, but of Jews, not of Gentiles, like that of Thessalonica before the coming of Paul (Grotius). Lydia was there, Acts 16:14. And in those neighboring places John preached for a long time, etc. (Ribera).
Thyatira was a city of Mysia or Lydia, not far from Philippi, the chief city of Macedonia; for Lydia, who traded in purple, and was of this city, went to Philippi to trade, as we read, Acts 16:12, 14.
[Who has eyes like unto a flame of fire] That is, who is most observant (Grotius), who sees the sins of Jezebel, which thou dost not see, or at which thou dost connive (Menochius): who shows His anger against that fornicatress, etc. (Ribera). See Revelation 1:14 (Grotius).
Eyes like unto a flame of fire: see Revelation 1:14, 15: it signifies either angry eyes, or quick and piercing eyes.
[And feet, etc.] As in Revelation 1:15 (Pareus). Whose actions are all pure and glorious (Grotius), just and uncorrupted; and whose power is irresistible (Durham): who will shatter, etc., enemies, as it follows here (Ribera).
The comparing of his feet to fine brass, seemeth to signify both the purity and holiness of his ways and methods of providence, and also his firmness and steadiness in them.
 Greek: Καὶ τῷ ἀγγέλῳ τῆς ἐν Θυατείροις ἐκκλησίας γράψον, Τάδε λέγει ὁ υἱὸς τοῦ Θεοῦ, ὁ ἔχων τοὺς ὀφθαλμοὺς αὐτοῦ ὡς φλόγα πυρός, καὶ οἱ πόδες αὐτοῦ ὅμοιοι χαλκολιβάνῳ·
 Carpus was an early Christian martyr, said to have been executed c. 160-169, during the reign of Marcus Aurelius and Lucius Verus.
 Acts 17:1.