Song of Solomon 5:2
Song of Songs1 The Lover to His Beloved: I have entered my garden, O my sister, my bride; I have gathered my myrrh with my balsam spice. I have eaten my honeycomb and my honey; I have drunk my wine and my milk! The Poet to the Couple: Eat, friends, and drink! Drink freely, O lovers! 2 The Beloved about Her Lover: I was asleep, but my mind was dreaming. Listen! My lover is knocking at the door! The Lover to His Beloved: “Open for me, my sister, my darling, my dove, my flawless one! My head is drenched with dew, my hair with the dampness of the night.”
Revelation 3:20
19 All those I love, I rebuke and discipline. So be earnest and repent! 20 Listen! I am standing at the door and knocking! If anyone hears my voice and opens the door I will come into his home and share a meal with him, and he with me. 21 I will grant the one who conquers permission to sit with me on my throne, just as I, too, conquered and sat down with my Father on his throne.
Notes and References
"... The imagery in the first part of Revelation 3:20 is widely thought to be dependent on Song of Songs 5:2, which has the two motifs of knocking for admission (on an implied closed door) and an appeal to the one within to open the door for the visitor ... When the beloved opens the door, however, the knocking suitor is nowhere to be found, even after a fruitless and dangerous outdoor search (verses 6–7), suggesting that the beloved had dreamed the whole episode (made explicit in the opening phrase “I sleep, but my heart is awake”). If this passage is the source of the imagery in Revelation 3:20, then the unhappy outcome has been passed over in silence: when the door was opened, no one was there. Judaism transformed the originally erotic poetry of the song of songs for inclusion in the biblical canon by interpreting the entire poem as an allegory of the love of God for Israel (b. Avodah Zarah 29a). Early Christians tended to read the song of songs analogously, probably influenced by Jewish exegesis ..."
Aune, David E. "The Polyvalent Imagery of Rev 3:20 in the Light of Greco-Egyptian Divination Texts" in Aune, David E. (ed.) Greco-Roman Culture and the New Testament: Studies Commemorating the Centennial of the Pontifical Biblical Institute (pp. 167-183) Brill, 2012