Answer from Randy Alcorn:

I still can’t get around Christ’s words in Matthew 22, which seem to clearly refute the Sadducee’s assumptions that if there were a resurrection, it would mean marital partnerships from earth would carry over to the resurrected life, and therefore people would have multiple spouses. Look at His words and consider the context:

The same day Sadducees came to him, who say that there is no resurrection, and they asked him a question, saying “Teacher, Moses said, ‘If a man dies having no children, his brother must marry the widow and raise up children for his brother.’ Now there were seven brothers among us. The first married and died, and having no children left his wife to his brother. So too the second and third, down to the seventh. After them all, the woman died. In the resurrection, therefore, of the seven, whose wife will she be? For they all had her.” But Jesus answered them, “You are wrong, because you know neither the Scriptures nor the power of God. For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven.”

Now, your position that in a perfect world https://brightwomen.net/es/mujeres-chinas/ there can be the essence of marital relationships without the institution of marriage is interesting. (There are points that can be made against it as well as for it.) But in any case, how does it point out the false assumption behind the question of the Sadducees? How does it explain Christ’s words? Taking your position, who will people be one with and have sex with and bear children with on the New Earth? Only their first spouse? Or all their spouses? If a woman is married to seven men who died, or some that divorced her and others that died, who is her partner in the resurrection? If the answer is all of them, why didn’t Jesus just say “All of them.” If it was only the first spouse, why didn’t he say “Her first husband’s”? That would have answered their question.

Again, you can say “but they won’t be husband and wife because there won’t be an institution of marriage.” Okay, then say “partner” or whatever you wish. Well, how does that solve the problem? It’s the same issue-which of the seven men will she be a partner with and bear the children of?

If someone argues that there will be sex and child-bearing with all seven men on the New Earth, how does that fit with the model of one man and one woman? If, on the other hand, it is just the first partner, doesn’t that suggest she wasn’t really one flesh in subsequent marriages? But if there is death and God led her to remarry, wouldn’t subsequent marriages be real in God’s sight too? (If they weren’t, how could God have been pleased with them?)

Why didn’t He say “There won’t be marriage per se but they will still be partners who will have sex and have children”?

And what if the woman’s first husband was a nonbeliever and will not be there in Heaven? Then will she not have an earthly partnership, while others will? Or will she be married to the first spouse she had that will be in Heaven?

Again, reading Matthew 22, I sense that the whole point is that Jesus gave an answer to the Sadducees that said they were wrong in thinking that earthly partnerships (call them marriage or one flesh or child-bearing relationships or whatever you would call them with your position) will continue in the resurrection. Then and only then does His answer respond to their question by telling them their question is based on invalid assumptions.