Donna Nielsen writes that a knowledge of scriptural marriage imagery can greatly enrich our understanding of how God relates to us through covenants. In the Bible we find that Jesus taught the people using examples of weddings and feasts, and of Himself as the Bridegroom. It was meaningful to the Jews in a way that it is not to us because we lack understanding of their culture
The marriage covenant was sealed with a cup of wine. Wine represented blood (Matthew 26:27-28) [hence its suitability for covenant making], sacrifice, and also joy. These three elements were intrinsic to the marriage relationship.
After all the negotiation and talk, a bride price settled, a gift having been offered, the man would then pour a cup of wine for the woman and place it before her. Now came the suspenseful part. At this point, the woman had about thirty seconds to make up her mind. If the woman was willing to receive the man and his proposed condition, she would accept his gift and also drink the cup of wine which sealed the covenant. This showed that she was willing to take his name upon her. This act had to be witnessed by two observers. Technically, once the above conditions were met, they were considered married. [Donna B. Nielsen, Beloved Bridegroom: Finding Christ in Ancient Jewish Marriage and Family Customs, pp. 2, 30]