We often talk about “inviting Christ into your heart,” but it may surprise you to learn that this is the only text in the New Testament that uses that sort of imagery, and it refers to Christ dwelling in the hearts of those who were already believers. It is not an evangelistic verse. In Revelation 3:20, Christ pictures Himself as standing at the door and knocking. He promises to come in and dine with anyone that opens the door. But the text never states that it is the door to your heart. And, He is speaking to those in the church of Laodicea, who already professed to be Christians. We may argue that they were not genuine believers. But in any case, they were associated with the church.