1) Jesus was perfectly clear-- marriage is when God brings a man and a woman together who are capable of sharing a one flesh union with the possibility of fulfilling the creation order mandate-- be fruitful and multiply (see Mk. 10/ Mt. 19).

2) Jesus was equally clear in Mt. 19 that the alternative for his disciples was celibacy in singleness, which is what 'being a eunuch for the kingdom' refers to.

3) In order to meet the requirements for being a husband according to the household
codes in Col. 3.-4 and Ephes. 5-6 one must: 1) be a male, and 2) have a partner who is a member of the opposite sex. Men cannot be wives, however much they may try and play such a role, nor can women be husbands, and a relationship that involves either two men or two women produces exactly NO husbands or wives.

4) The only couple capable of being a father and a mother of their own biological children is a man and a woman. Adoption only makes a person a surrogate father or mother at best. And if one person is the biological parent of the child, whereas his or her partner is not, then in fact one has deprived the child of either their birth mother or their birth father. They have come to have a child 'out of wedlock', if one counts either gay or lesbian relationships as marriage.

5) A child deserves to have both a mother and a father, and more particularly their own biological parents if humanly possible. Any relationship which involves two mothers (one of whom is not the real mother) or two fathers (one of whom is not the biological father) does not provide the modeling of what a husband and wife/mother and father relationship should look like under any sort of normal circumstances.

6) Same sex sexual activity, whether between consenting adults or through some other sort of relationship, is clearly defined as a sin in both the OT and the NT, indeed a serious sin. If this is correct, then gay marriage is a non-starter.

7) There is an irreducible biological or gender component to being a man or a woman. One does not get to choose one's biology, one's XY chromosomes. The creation story in Gen. 1-2 makes perfectly clear that the only 'suitable companion' for the man was a woman, and this is because God created us male and female in his image. Only so could we perpetuate the human race. Only so could we be mini-creators of more human beings, so mirroring one aspect of God the Creator.

At the end of the day either we realize that gender matters, and gender difference is essential to a real Christian marriage, or we totally change the definition of what counts as marriage, what counts as husband and wife, what counts as mother and father Biblically speaking. It is in no way surprising that in the most individualistic and narcissistic culture on the planet, that Americans would like to be able to even choose their gender, their own biology. But in fact you can't do that, and since gender matters Biblically speaking when it comes to Christian marriage, you also do not have Biblical permission to redefine marriage, husband, wife, mother or father.

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