“He who has the bride is the groom. The friend of the groom, who stands and hears him, rejoices with joy at the voice of the groom. ( John 3:29.)
The best man says those things about the groom, the voice about the Word, the light about the sun, John about Christ. Indeed, ‘the groom’ is Christ, and ‘the bride whom he has’ is the church. David says about him, He has set his tabernacle in the sun; he is like a groom coming out of his chamber. (Psalm 18:6) Solomon speaks about the bride, You have wounded my heart, my sister; my woman, you have wounded my heart. (Canticles 4:9) For, we remember that we distinguished four types of betrothal in the tract which we undertook, On the fourfold types of marriage. The first is between a husband and a legal wife, the second is between Christ and a holy church, the third is between God and a righteous soul, the fourth is between the Word and human nature.”  Pope Innocent III, Sermon on John 3:29