A public discourse that recuses from any reference to a supreme and ultimate and ultimately binding moral order – that is, i.e., morally relativistic – forecloses any possibility of investing any public act with true and perfectly general meaning. When there is nothing that must in virtue of its factual meaning under the highest heaven certainly mean therefore at least one same thing to everyone beneath the orbit of the moon, nothing can mean the same thing to anyone except by happenstance, or by the constraints ever imposed upon all creatures by the logos of corporeal becoming (as, e.g., when the flood approaches and everyone feels it truly and existentially important and valuable to flee, regardless of their politics or sexual identification).
To put it bluntly: if you can’t talk of God and his will for us in a language that everyone understands and accepts (even if only pro forma), then nothing you say can be quite definite, in the final analysis, or therefore definitive, or then authoritative, or suasive. Every utterance then will be tentative, merely pro forma and nothing more; ergo, not really binding, or even interesting, but only conventionally. At most, you’ll muster only indignant insistence about this or that outrage, full of sound and fury but, as signifying really nothing, empty of any real conviction.