A bell rings. A bird tweets. A few notes from a song suddenly play. A xylophone trills. A frog croaks. Gentle sounds, musical sounds, funny sounds. Curiously, all of them seem to demand attention. Text messages are coming in! People drop what they're doing. They must be urgent! Many people in the Old Testament received urgent messages too, but they didn't come with ringing bells or tweeting birds or trilling xylophones. They came from bold, determined,...