I summed my side up with rare serenity in, "The folly of mistaking a metaphor for a proof, a torrent of verbiage for a spring of capital truths, and oneself as an oracle, is inborn in us, Mr. Valery once said."
There are no more uses of "serene" in the book.
Show samples from other sources
While I lie awake worrying, she sleeps serenely.
She remained serene even when he was yelling at her.