Riffing on Charles Taylor's "Secular Age" & @TheAlanNoble's "Disruptive Witness": We live in a secular age where the possibilities of belief are endless and all beliefs are contested. Open-mindedness becomes a virtue b/c, "How can you be certain you're right & others are wrong?"
Resulting attitude: Anyone who receives his/her beliefs from parents is automatically suspect & treated with skepticism b/c given all the options out there, it's ridiculous to just accept as a given what you're raised to believe. It's inauthentic & narrow.
Problematic church response: No one is an authentic Christian unless they have a testimony explaining how they individually came to faith. This must include a personal commitment made apart from family upbringing at a time when the person has a degree of independence.
Observation: IMO this explains why Baptist ecclesiology seems commonsensical to so many Americans. The idea that a person receives an identity (i.e. through baptism) from his/her parents & grows up in this goes against the secular/American disposition.
Conclusion: Part of being faithful in a secular age as a church is combatting this nonsense about received identity and faith being problematic. Infant baptism is actually one of the most important ways we combat secularism while decisionism plays into it.
We must raise covenant children in the faith deeply embedded in the practices and community of the church.
