The document is a poem that encourages the reader to smile even when facing sorrow or fear. It suggests that by smiling through difficult times, the reader may find the sun shining through tomorrow and that life remains worthwhile if they maintain a positive outlook through smiling. The poem repeats that even when sadness feels near, the reader should light up their face with gladness, hide traces of sadness, keep trying, and understand that crying serves no purpose when smiling can help them see the worthwhile aspects of life.