Is it permissible to purify oneself with water that has mixed with a small amount of impurity that has not altered any of its characteristics?

The impurity that falls into water has three states:

1. If the impurity changes one of the water's characteristics (color, taste, smell): The water becomes impure by consensus, whether it is little or much.

2. If the impurity falls into a large quantity of water and does not change its characteristics: The water remains pure by consensus.

3. If the impurity falls into a small quantity of water and does not change its characteristics: The correct opinion is that the water is not judged impure unless it is changed by the impurity, whether the water is little or much. This opinion is based on the hadith: "Indeed, water is pure; nothing makes it impure."

However, to be cautious in religious matters, one should avoid using a small quantity of water into which impurity has fallen, even if its characteristics have not changed, especially if the water is very little.