Revelation 3:13-15

Amplified Bible

¹³He who has an ear, let him hear and heed what the Spirit says to the churches.’

¹⁴“To the angel (divine messenger) of the church in ^[a]Laodicea write:

“These are the words of the Amen, the trusted and faithful and true Witness, the ^[b]Beginning and Origin of God’s creation:

¹⁵‘I know your deeds, that you are ^[c]neither cold (invigorating, refreshing) nor hot (healing, therapeutic); I wish that you were ^[d]cold or hot.

Revelation 3:14 Laodicea, located beside the Lycus River, was a prosperous city about forty miles south of Philadelphia. It had a well-respected financial center, thriving textile production industry (specializing in black wool), and a leading medical school that produced a famous eye salve. Two other cities were in this general area: Colossae, known for its mountain spring of cold, fresh water; and Hierapolis, a site famous for its hot, therapeutic mineral springs.
Revelation 3:14 I.e. Origin of Source.
Revelation 3:15 This phrase and the word lukewarm in v 16 form a metaphor that is probably based on the quality of the water supply of Laodicea, which was delivered by aqueduct from the hot mineral springs about five miles away. During its journey, the water cooled to a warm or lukewarm temperature.
Revelation 3:15 I.e. alive, productive—beneficial in one way or the other.