The idea for the song had been with Berlin for years, and he knew that the finished work was momentous. He told his assistant that “White Christmas” was the best song he had ever written, possibly the best song anyone had ever written. Yet not even he gauged its full potential, its emotional resonance. Berlin received little encouragement from Sandrich and Paramount executives who heard him audition the score in September (when Bing was in Buenos Aires). They shrugged. They figured the score’s hit would be the Valentine’s Day ballad, “Be Careful, It’s My Heart.”
Crosby admired it from the start, a sanction for which Berlin remained grateful, often repeating the story of the day he auditioned the songs to get Bing’s okay. “I was nervous as a rabbit smelling stew. I sang several melodies, and Bing nodded quiet approval. But when I did ‘White Christmas,’ he came to life and said, ‘Irving, you won’t have to worry about that one.'”