It means purification of feelings and desires to reach the most sublime form – goodness. To dream of slow, steady raining foretells that the benefit will be great but slow to arrive. If it’s a downpour that has us immobilized it means there will be interference or problems that need to be solved before achieving those benefits. This dream indicates that the greater amount of rain water means a greater benefit.
Read more about dreaming of Rain in other dream meanings interpretations.