One key aspect of this unveiled mystery is that the family structure is not an arbitrary expression fo the will of God, but is an icon of God’s purpose of the universe in Christ.
Onward p. 166
It’s not arbitrary, nor is it just one of many ways to make a family, as our culture would like us to believe. The culture has doubled down like hypocrites often do: You must recognize my way of doing things, but heaven forbid—at least for now—that you recognize that way of doing things. Polygamy—at least for the time being—is still on the edges, but there’s no logical reason it should be if we choose to jettison God’s purpose for the family.
Lingering Over Leaves 