In preparation for her presentation to Christ, her Spouse, the Church undergoes a “washing of water” which leaves her glorious, “without spot or wrinkle or any such thing, that she might be holy and without blemish” (Ephesians 5:26-27). What is this “washing of water?” Many commentators on Ephesians have identified this “washing of water” with the Jewish wedding ritual known from rabbinic sources as the bridal bath. While this may seem an obvious allusion at first blush, it is highly unlikely since there is no evidence that such a tradition existed until medieval times.
Others have suggested that the washing is symbolic for the cleansing power of the blood of Christ or the outpouring of the Holy Spirit on the day of Pentecost. These interpretations are appealing based upon the comparison of this passage with other Scriptures that speak of cleansing by the blood of Christ (e.g., 1 John 1:7; Revelation 7:14) or that use water symbolism to denote the Holy Spirit (e.g., John 7:37-39). However, while these interpretations are not impossible, they seem to make the explicit reference to water superfluous and are nowhere suggested in the immediate context. G. R. Beasley-Murray’s judgment regarding these interpretations is, I believe, correct: “If this is intended as an exposition of Eph. 5:25 ff., rather than a theological construction taking its point of departure from the passage, it is hardly to be received.” So where do we go from here? I believe this is where it is helpful to listen to the text, textual antecedents in the Old Testament, and early Church liturgy according to the New Testament.
The Greek words Paul used for “washing of water” are the same used in the Old Testament for the ritual lustrations prescribed for cases of uncleanness (Lev. 15). Numbers 19 dictated the same ritual ablution using a hyssop branch dipped in water with which to sprinkle the unclean person. That this was understood as moral cleansing, and not merely external ceremony, is evidenced in David’s penitential Psalm after being confronted by Nathan concerning his adulterous affair with Bathsheba: “Purge me with hyssop, and I shall be clean; wash me, and I shall be whiter than snow” (Psalm 51:7). The prophet Ezekiel makes the explicit connection between these purification rites and the spiritual renewal brought about by the Spirit of God: “I will sprinkle clean water on you, and you shall be clean from all your uncleannesses, and from all your idols I will cleanse you. . . . And I will put My Spirit within you, and cause you to walk in My statutes and be careful to obey My rules” (Ezek. 36:25-27; cf. Zech. 13:1). There can be little doubt that John’s “baptism of repentance for the forgiveness of sins” had this rite and its eschatological promise primarily in view (Luke 3:3). Yet, even John the Baptist recognized that his was not the final cleansing (baptism) spoken by the prophets: “He who is mightier than I is coming, the strap of whose sandals I am not worthy to untie. He will baptize you with the Holy Spirit and with fire” (Luke 3:16). Baptism and the inward cleansing of the Spirit are conjoined in the earliest record of the post-resurrection Church: “And Peter said to them, ‘Repent and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins, and you will receive the gift of the Holy Spirit” (Acts 2:38; cf. Acts 22:16; 1 Pet. 3:21).
Because baptism was inextricably tied to the proclamation of the gospel from the earliest days of the post-resurrection Church (Matt. 28:19) and clearly spoke of moral cleansing, baptism seems the most likely referent of “the washing of water” in Eph. 5:26. Of course, this washing of water is “with the word,” namely, the gospel of Christ. Without the gospel baptism would be an empty ritual, a sign with no significance. But with the gospel baptism is a means of grace that brings the cleansing of sin and renewal by the Holy Spirit. Since every member of the Church is thus baptized, she is the Bride who has been cleansed by “the washing of water with the word,” presented to Christ in glory.
 G. R. Beasley-Murray, Baptism in the New Testament (Grand Rapids: Eerdmans, 1962), 201.
 See J. V. Fesko, Word, Water, and Spirit: A Reformed Perspective on Baptism (Grand Rapids: Reformation Heritage Books, 2010), 202-227.