To justify Christian morality because it provides a foundation of morality, instead of showing the necessity of Christian morality from the truth of Christianity, is a very dangerous inversion.
If the assertion that there is a god is nonsensical, then the atheist's assertion that there is no god is equally nonsensical, since it is only a significant proposition that can be significantly contradicted.
Sins are indispensable to every society organized on an ecclesiastical basis; they are the only reliable weapons of power; the priest lives upon sins; it is necessary to him that there be sinning.
Thought that is silenced is always rebellious. Majorities, of course, are often mistaken. This is why the silencing of minorities is necessarily dangerous. Criticism and dissent are the indispensable antidote to major delusions.