In the temple (and tabernacle) of the Old Testament were two altars. A bronze one stood in the courtyard in front of the temple where sin offerings and burnt offerings were made (Exodus 27:1–8); a golden altar stood inside the temple before the veil where incense was offered (Exodus 30:1–10; 2 Chronicles 2:4) representing the prayers of the people (Psalm 141:2). The altar John must measure is the golden altar of incense, not the bronze altar outside. We know that because John had already spoken of this altar at the beginning of this series about the trumpets (Revelation 8:3–4; see also Revelation 6:9); if John were to measure the other altar it would have been clearly said. In measuring this golden altar of incense John is meant to pay attention to (measure) the prayers of the saints—those who are the temple of God, the church. Those prayers, of course, are what prompt the blowing of the trumpets and thus initiate plagues on earth (Revelation 8:6).