That's the trailer for "Bells of St Mary's," a 1945 film, featuring Bing Crosby and Ingrid Bergman, that won one Academy Award and was nominated for nine others. It's one of those old movies you can enjoy with your children and grandchildren without being embarrassed.
The final scene in the movie is, in my view, one of the greatest love scenes ever to come out of Hollywood. Love, that is, in the sense of Agape, which has been defined as: the highest and purest form of love, one that surpasses all other types of affection.