Which church in Revelation is identified as needing to repent?

The church identified in Revelation as needing to repent is the church of Sardis. This church is highlighted in Revelation 3:1-6, where it is described as having a reputation for being alive but is actually dead. The call to repentance is a clear directive, urging the church to wake up and strengthen what remains before it entirely fades away. In the context of the other churches mentioned, while Pergamum does face criticism for holding to false teachings, it is Sardis that receives the specific admonition to repent for its spiritual condition.

The other churches, such as Thyatira and Philadelphia, receive mixed messages regarding their faithfulness or encouragement for their perseverance, but Sardis is explicitly directed to address its shortcomings through repentance. This makes it unique among the options provided, emphasizing the importance of genuine spiritual vitality and the call to return to a state of faithfulness.