The clearest passage describing the Bride of Christ, calls it a mystery (Eph. 5:32). That in itself should tell us maybe we shouldn't be too dogmatic when speaking of Christ's bride. The word "bride" appears only seven times in the New Testament, three of which refer to the bride chamber. The only time it is used in the Gospels is found in John 3:29 where John the Baptist refers to the Christ as the bridegroom, but he is speaking to Jews. God viewed Israel as His bride (Jer. 3:14). So John's reference to Christ, Who is God, most likely has to do with His relationship to Israel.
Jesus referred to "bridegroom" eleven times, and although He does not specifically say that He is the Bridegroom, in most cases it is clear that He is speaking of Himself (Matt. 9:14-15; Mk. 2:19-20; Lk. 5:34-35). With the exception of Matthew 25:10-13, all His references are in response to the criticism of the Pharisees over His disciples failing to observe the fast. In Matthew, He describes the Second Coming as His return as the Bridegroom (Matt. 25:1-13). Paul speaks of the Church being "espoused" (engaged) to Christ (2 Cor. 11:2). In the Ephesians passage mentioned above, Paul describes the relationship of a husband and his wife to that of Christ and the Church.
From the Old Testament view that Israel was the bride of Jehovah, and the New Testament presenting the mystery of the Church being the Bride of Christ, one might get the impression that God is a bigamist. Obviously that is not the case because, even though He permitted men to take more than one wife in the Old Testament, it was not what He intended. The New Testament clearly teaches that a believer is to have only one wife if he would be considered a spiritual leader (1 Tim. 3:2; 3:12; Titus 1:6). Certainly man can not be considered more spiritual than God!
Perhaps the answer lies in Revelation where the marriage takes place (Rev. 19:7-9); the description of the Bride as being "the holy city, new Jerusalem" (Rev. 21:1-2); and the description of the New Jerusalem, itself (Rev. 21:9-14). The Lord's Bride consists of all of those saved by grace through faith in Jesus Christ, both Jew and Gentile. Paul wrote that there is no longer a separation between Jew and Gentile, but both are united in the Body of Christ (1 Cor. 12:13; Gal. 3:28; Eph. 2:13-16). The New Jerusalem is made up of twelve gates representing the twelve tribes of Israel, and twelve foundation stones representing the twelve apostles (Rev. 21:12-14). So, the best I can do to explain why Israel is married to Jehovah, and the Church is married to Christ, is found in the composition of the Church. Just as both represent the Bride, Jehovah and Jesus (One in the Same in my opinion) are the Bridegroom.