What is the meaning of sins coming out with water or with the last drop of water?

The mentioned hadith is authentically reported in Sahih Muslim, and its purport is that ablution expiates sins related to the organs of ablution, until the person performing ablution emerges pure from sins. Scholars have differed on the meaning of "or" in the hadith, whether it indicates doubt on the part of the narrator or signifies one of two possibilities. They have also differed on the meaning of "sins exiting with the water," whether it is a metaphor and an idiom for the forgiveness of sins, or a reality such that sins cause a darkness that ablution removes. Some have supported the latter, citing hadiths that show sins affect and blacken the heart of the servant, and that purification removes that blackness.