"Never think of the family — the nuclear family: husband, wife, and children — as the only or the eternal or the main family with which God is concerned. The church is God’s main family on the earth. In the age to come, there will be no nuclear family because Jesus says in that age that we will “neither marry nor are given in marriage” (Matthew 22:30). The nuclear family is temporary. The eternal family is the church with God as our Father and all of us as brothers and sisters.
I want to elevate this. She didn’t mention the church, but I’m sowing the seed for her to think about it. I want to elevate the local church as the expression of God’s family for her life. That’s precisely where she should embed this child in relationships with the wider family — men, women, boys, and girls — so that the child will connect in all the varying ways that he’s going to need in order to be as rounded as he should be."~~"Ask Pastor John"
There is no OT or NT word that can mean 'nuclear family '.
Schaeffer critiqued the Enlightenment for its fact/value split where "nature swallowed up grace." Christians have overreacted, claiming that grace swallows up nature. Eschatologically yes. Presently, no. That's why we have families and the state.
Gnostics are always trying to minimize the importance of flesh and matter and all earthly existence and relationships. The same cast of characters is teaching women that their husbands have no real authority over them, so that if he tells her to do something she doesn't want to do, the "church," meaning the elders, are to arbitrate. And of course, they teach that there are only two races, Christians and non-Christians, so that faith is all that matters, and any concerns over optimal government, borders, social bonds, marital restrictions, etc, are idolatry.
John Piper's point winds up being self refuting.
"The eternal family is the church with God as our Father and all of us as brothers and sisters" --- this presupposes the comprehensibility of nuclear family.
Restated: Without the earthly family, the concept of father, brother, sister, etc. are meaningless, and incomprehensible.
Restated: The family is God's main family on Earth without which the church "family" is incomprehensible.
The Church is both a spiritual and institutional entity on earth. It is built upon families that constitute its membership. It is a 'one and many', or a Trinitarian wholeness. Each Christian and/or family is one of the building blocks as equally ultimate to the whole, which is the Church on earth.