The Hadith stating that Wudu' is invalid if there is paste, nail polish or mud on the fingers

Q: It is reported that the Prophet (peace be upon him) said that Wudu’ (ablution) is not valid if there is paste, nail polish, or mud on the fingers. (Part No. 5; Page No. 218) However, I saw some women putting henna on their hands and feet - and this is a paste - and they perform Salah (Prayer) with it. Is this permissible, bearing in mind that when they are forbidden to do it they say that it is Tahir (ritually pure)?

A: All praise be to Allah Alone, and peace and blessings be upon His Messenger, and his family and Companions. There is no Hadith reported that carries these words, as far as we know. What remains on the hand and feet from henna is just its color, and this does not have any effect on Wudu’, as this has no thickness as paste, nail polish, or mud do. These things have a thickness that prevents water from reaching the skin. Therefore, it is not permissible to perform Wudu’ if these things remain, because they prevent water from reaching the skin. However, if the henna is a thick substance on the hands or feet which prevents water from reaching the skin, it should be removed in the same way paste and the like should.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.