What is the meaning of "Ayn al-Najasah" (the essence of impurity) in the Maliki madhhab, and does impurity transfer from a carpet that became impure due to vomit or other substances, and whose trace has disappeared, to dry or wet clothes, knowing that there are obsessive doubts?

The "ayn (physical manifestation) of impurity is anything that has a visible body or a discernible characteristic (such as color, taste, or smell) from substances that Islamic law has deemed impure, such as carrion, blood, and excrement.

Maliki jurists simplify this matter by stating that impurity does not transfer if its physical manifestation has disappeared, even by drying, and only its legal ruling remains. So, if something wet comes into contact with it, it does not become impure thereby, because a legal ruling does not transfer.

The drying of urine on a garment or other object is not considered the removal of impurity according to the well-known opinion of Maliki jurists. However, some of them have made it easier and generalized the ruling to include the drying of all impurities.

Based on this opinion, it is not ruled that impurity has transferred to you, and you are not required to perform ghusl (ritual bath) before every prayer. Rather, what is obligatory is to wash the area that is certainly known to have been affected by the impurity.

Strive to purify impurities as much as possible, and beware of the danger of waswasah (obsessive doubt) and its great harm, for giving in to it is one of the biggest causes of corruption in both religious and worldly affairs.