Believe it or not, there are many theories concerning the identity of the Bride of Christ. Without taking up time and space here, suffice it to say that they range from the logical to the ludicrous. My hope is, if I let the Word speak for itself, the truth will be obvious.
In Ephesians 5:22-33, the Apostle Paul uses the Lord's relationship to the Church as a pattern for how Christian marriages should work. Just as the Church should submit to the Lord, a wife should submit to her husband (v. 22, 24). Clearly, Paul is describing the Church as the Bride of Christ. He also describes the Lord's relationship to the Church as a mystery, and as a pattern for the oneness of the husband and wife (v. 32). When the two become one flesh, the husband is "the head of the wife", just as Christ is the head of the Church, His body (v. 23, 28-31). And finally, Paul admonishes husbands to have the same love for their wives as Christ has for the Church (v. 25-27).
Some have suggested that the Church cannot be the Bride of Christ, because the Old Testament declares Israel to be the Lord's wife. When Israel broke its covenant with God, He declared Israel to be adulterous (Ezek. 16:1-68). Because Israel broke its covenant with her Husband, God divorced her (Jer. 3:8). Jesus called Israel "an adulterous generation" (Matt. 12:39). But just as God's relationship to Israel is described in the Book of Hosea, when the covenant is renewed, it will be like a remarriage (Hosea 2:7). There is irony in the Ezekiel passage, because it is addressed to Jerusalem (v. 2); the new Jerusalem appears as a bride in Revelation 21:9-14:
"And there came unto me one of the seven angels which had the seven vials full of the seven last plagues, and talked with me, saying, Come hither, I will shew thee the bride, the Lamb's wife. And he carried me away in the spirit to a great and high mountain, and shewed me that great city, the holy Jerusalem, descending out of heaven from God, having the glory of God: and her light was like unto a stone most precious, even like a jasper stone, clear as crystal; and had a wall great and high, and had twelve gates, and at the gates twelve angels, and names written thereon, which are the names of the twelve tribes of the children of Israel: on the east three gates; on the north three gates; on the south three gates; and on the west three gates. And the wall of the city had twelve foundations, and in them the names of the twelve apostles of the Lamb.
Isn't it neat how the apostles are in place first, and then the patriarchs are placed upon them? This suggests to me that the new Jerusalem begins with the apostles, representing the born again Jews and Gentiles who make up the Church, and then the nation of Israel is added when "the times of the Gentiles" is passed, and their eyes are opened to Jesus being their Messiah (Rom. 11:1-36). God is so awesome!