Of born Protestants whose parents talked about religion “a lot,” 89 percent continue to identify as Protestant. . . . The “raised religious” who are leaving organized religion aren’t, for the most part, those whose parents found purpose and meaning in regular observance. Rather, they’re the children of people who, for whatever reason — social expectation, a sense of obligation, a sense that religion was “what one does” — felt the need to publicly identify with something they felt was privately insufficient.
(Tara Isabella Burton, Strange Rites [New York, NY: Public Affairs, 2020], 54, 55)

Why are 2nd and 3rd generations leaving the church? This is one of the issues that Graceworks is attempting to grapple with through our Generations Project. Something I read recently seems to confirm our findings (see above). A key reason children from Christian homes leave the church and the Christian faith is because they see that their parents don’t really believe that the Christian faith is real in the realities of daily life. These parents may be very active in church and very enthusiastic in church activities, but at home, their faith doesn’t really feature when the real decisions are made about behaviour, money, career choices, attitudes to other races, etc. A constant diet of this, and the child decides that the Christian faith is not real. We must also remember that in an internet age, many other voices are calling out to our young, promising to give meaning and purpose.
I note that Paul has this to say to Timothy when he was encouraging him to take seriously the veracity of Scripture.

But as for you, continue in what you have learned and have become convinced of, because you know those from whom you learned it, and how from infancy you have known the Holy Scriptures, which are able to make you wise for salvation through faith in Christ Jesus. (2 Timothy 3:14–15 NIV)

And who taught Timothy the Scriptures? His mother and grandmother (2 Timothy 1:3–5). That means the primary context where Timothy learned the Word was family and home. (Why isn’t Timothy’s father mentioned? Perhaps he was a gentile or had passed away). In other words, Timothy could see that the Word was true because he saw it being lived out in the home. There was no public display of piety that was different from the living out of the faith in private. 
However, the primary shaping of the faith of our Christian young has been taken over by the church through platforms like Sunday School. As my colleague Wei Hao often says, when the child comes home from Sunday School, parents will ask what they learnt in Sunday School. It should be the other round, he says. When the child shows up in Sunday School, the Sunday School teacher should be asking, “What did your parents teach you about the faith during the week?”
We need to seriously heed the call to return to the family as the primary context for shaping the faith of our children. There are issues to be worked out of course. What about the children who come from homes where the parents are not believers? Can they be part of extended families of the homes of believers? Or can we create family units made up of caring older singles who serve as spiritual parents of children who come from non-Christian homes?
One thing we need to do is to provide some basic training. First, we need biblical teaching which shows that the family as the primary platform for nurturing faith is actually the norm which can be complemented by Sunday School, but not the other way round. Then we need to provide practical guidelines as to how one can actually do this. It cannot be a one-size-fits-all approach because each child is different and each family context is different. Indeed, the church and families will be embarking on a learning journey where no one is the expert who has the last word. The church cannot pass this responsibility to parents and wash their hands of any responsibility. The church will have a critical role to play to encourage and equip families as they seek to nurture the faith of their children.
This approach to nurturing the faith of the young is, finally, a test of whether folks actually believe in Christ and the Bible. If Christianity is just a series of things we do on Sunday in the church building and not something we truly believe — something we live and die for — then no amount of teaching and training will count for anything.
The Covid pandemic has forced us to stop and re-evaluate what we really believe and how best to live out our faith. If we really love our children and want them to grow up with a vibrant faith, are we willing to pay the price?