His artistic approach favoured quiet genre scenes and domestic interiors. In works like "Interieur met man die voorleest aan een zieke in bed," Dekker captures a specific sense of stillness. He used a muted palette to define the space of a room or the soft shadows beneath trees. His figures often appear in moments of repose or private reflection to create a sense of quietude.

Modern collectors value Dekker for his ability to find interest in ordinary settings. These prints offer a window into nineteenth-century Dutch life without the sentimentality found in some Victorian works. The clear compositions and calm subject matter make these works suitable for a study or bedroom. His art provides a connection to the realist tradition of the Hague School while maintaining a personal focus on the individual.