Whatever separates the earth from what is given the name earth, if it is in the earth, there is a difference in it, except for the dirt, as we mentioned. This purity may be an independent act of worship, as he, peace and blessings of God be upon him, said, in which there is light upon light, and it may be a condition for the validity of a specific, lawful act of worship that is not valid. That worship is lawful except for its presence or preference. The first is like ablution upon ablution, light upon light, and the second is to remove the impediment to the act of worship that is not valid except with this purity and the permissibility of doing it, which is the basis for its legislation. Among what this purity occurs is that which removes the impediment and makes the act permissible together, which is water, without disagreement, and date wine. In ablution there is a difference, including what makes it permissible for the specific act at the time it is supposed to take place, and