His angel

Thinking about that, he came to the house of Mary, the mother of John who was called Mark, where many were gathered together and were praying. When Peter knocked at the door of the gate, a servant girl named Rhoda came to answer. When she recognized Peter’s voice, she didn’t open the gate for joy, but ran in and reported that Peter was standing in front of the gate. They said to her, “You are crazy!” But she insisted that it was so. They said, “It is his angel.”

Acts 12:12-15

Rhoda tells those praying at Mary's house that Peter is at the gate; they say it is his angel.