Hi, I am researching the topic of marriage according to the scriptures. My question is: What constitutes marriage? Before you answer I want you to know that I am aware of how this question is not easy to answer. I have been researching it for days now and still have not been able to make up my mind.
There are a couple theories out there and the one that seems most evident is the hypothesis that the act of consensual sexual intercourse between a man and a virginal female constitutes marriage. Of course, I don't want to lead your answer so please feel free to answer how you wish. I ask that you use scripture references if applicable.
Part of the reason this question is tough is that there are a few kinds of marriage mentioned in scripture (at least 3 or 4), though there is really only 2.
The for kinds are:
1) Natural Marriage - From the beginning, one man and one woman, each possessing half of a reproductive system, and when joined as one becoming a life-giving image of the trinity. Ceremony is important, as we live in community, but the marriage was primarily effected between the two parties (the man and the woman), and was generally final once consummated (i.e., once they had had sex).
2) Polygamy - Never really endorsed, from the first guy, Lamech, in Genesis, who takes two wives and is a murderer, to kings like Solomon, who had hundreds of wives (and got in a lot of trouble over it)
3) A "Josephite marriage", unique to Mary and Joseph, who lived their lives chastely before, during, and after their marriage. Joseph was likely an older widower, possibly even with other children, and Mary was planned to be a consecrated virgin of a sort it would seem. There weren't religious orders back then (i.e., Nuns or Sisters), so women who chose to dedicate their lives in this way had to find a patron, often an older widower.
We can tell that their relationship was this way from Mary's response to the Angel in Luke 1. The angel comes bearing a prophecy that she WILL conceive (in the future) and bear a son, and Mary, betrothed to Joseph, doesn't say "Oh, with my Husband," but rather, "How can this be, since I do not know man." She was consecrated, but her marriage to Joseph was still a marriage, nevertheless, even though it was not consummated through the conjugal act (sex).
4) A sacramental marriage. Jesus clarifies to the pharisees that "what God has joined, no one may separate," and Paul reiterates that marriage between two baptized believers is elevated beyond Natural marriage, and is in no way dissolvable, unlike a natural marriage (between two non-believers, or a believer and a non-believer) which MAY be dissolved, but ought not to be unless circumstances warrant. (Cf. 1 Cor 7: "If any brother has a wife who is not a believer and she is willing to live with him, he must not divorce her. And if a woman has a husband who is not a believer and he is willing to live with her, she must not divorce him. For the unbelieving husband has been sanctified through his wife, and the unbelieving wife has been sanctified through her believing husband. Otherwise your children would be unclean, but as it is, they are holy.").
A sacramental marriage more perfectly mirrors the "one-ness" hinted at from the beginning (Genesis 1 - "the two become one flesh") which is meant to be an image of the trinity (three persons, one being, life giving, defined by love and it's life-giving properties).
In all cases, sexual intercourse seems to be the final straw that pushes the relationship into marriage status. Your question hinted upon a virginal female, but I don't think that's necessary, as both in the Old Testament, and the New, it is spoken of that widows and widowers can remarry (Paul even hints that they SHOULD if they're younger, but if they're older they should consecrate themselves and live chastely in an order of what is essentially 1st century nuns!
(cf. 1 Tim 5:9ff: "Let a widow be enrolled [in this group of chaste women] if she is not less than sixty years of age, having been the wife of one husband, and having a reputation for good works: if she has brought up children, has shown hospitality, has washed the feet of the saints, has cared for the afflicted, and has devoted herself to every good work. But refuse to enroll younger widows, for when their passions draw them away from Christ, they desire to marry and so incur condemnation for having abandoned their prior [of celibacy in joining this order, NOT their ended marriage, as Paul clearly says that they CAN licitly remarry, as he says:]. ... I would have younger widows marry, bear children, manage their households, and give the adversary no occasion for slander.")
(cf. 1 cor 7: "So then, he who marries the virgin does right, but he who does not marry her does better. A woman is bound to her husband as long as he lives. But if her husband dies, she is free to marry anyone she wishes, but he must belong to the Lord. In my judgment, she is happier if she stays as she is—and I think that I too have the Spirit of God."