Christian parents guilt-ridden (wrongly) over wayward adult children, believing (wrongly) that proper rearing is the exclusive condition of children’s faith might be comforted by the knowledge that the first Father’s children ruined the human race, despite living in a sinless environment, and that the same Father grieved in his heart:
“Hear, O heavens, and give ear, O earth!
For the Lord has spoken:
“I have nourished and brought up children,
And they have rebelled against Me” (Isa. 1:2)
If one wishes to argue that God was a parental failure with Adam, Eve, and Judah, well, good luck with that.
Christian training is usually a necessary, but never a sufficient, condition of Christian adulthood. We all know converted adults who were not trained in the Faith, as well as wayward ones who were. Christian training is worthless if not tethered to a heart wholly devoted to Jesus Christ.
God’s covenant stipulations are conditional at every point, and any view that suggests covenant inclusion or covenant training is an ironclad guarantee against backsliding or apostasy knows nothing of biblical covenantalism (Deut. 28–30).
Christian parents of wayward adult children may — or may not — be at fault.
The warnings of covenant apostasy are not applicable only to adults whose parents failed. They confront also at every point adult children reared in the Faith.
Parents, if you were substantively faithful in rearing your children who currently violate the covenant, abandon all feelings of guilt — and pray in fearless faith that the God who rejoices to shower his grace brings your prodigal home.