Question 638: Salaam. I would like to know if it is necessary to wash hand/feet with soap for wudhu if we have applied lotions/creams containing oil. Also, is wudhu/ghusl valid if we have applied chemical henna that forms a layer which peels of later? You think Applying Henna or cream before Wudu is considered as a barrier to water reaching the skin?
Answer 638: If the effect of lotion or cream that left on the skin after it is applied is nothing but just moisture, and so it does not constitute a barrier to water reaching the skin. Otherwise, you should wash it with soap or any other thing before you want to perform Wudhu, Ghusl or Tayammum.It is said that everything which is considered as a barrier to water reaching the skin must be removed before performing Ghusl, Wudhu or Tayammum. So, as for your second question, it is known that applying a material which is considered just a color on the skin, such as henna, does not nullify Wudu. It is, however, said that other materials that make a layer on the skin that prevents water from reaching the skin are to be removed for wudu, Ghusl or Tayammum.
For further information in this regards, please refer to the following answers:
Index: Number of things which invalidate Wudu (ablution), answer 556.
Index: Makeup after wudu doesn’t void prayer, answer 157.
Index: Using products with animal ingredients if they are ritually impure, answer 104.
Index: Doubts during prayer whether wudu was performed or not, answer 036.
Index: Wiping performed on socks invalidates Wudu, answer 037.
Index: Impermissibility of making Wudu after Ghusl, answer 035.
Index: Making Wudu when you are going to bed, answer 032.
Index: The validity of Ghusl even a barrier finds out after a week, answer 031.
 . Ajwabat al-Istiftaat of Ayatollah Khamenei, Q. 104; Jame al-Masael of Ayatollah Fazel, Vol. 1, Q. 125; Istiftaat of Imam Khomeini, Vol. 1, Chapter on Wudu, Q. 40; Jame al-Ahkam of Ayatollah Saafi, Vol. 1, Q. 91-106; Istiftaat of Ayatollah Tabrizi, Q. 152; The official website of the office of Sayyid Sistani, Q&A. Nail Polish.
 . Tawzih al-Masael of maraja (annotated by Imam Khomeini), Vol. 1, Pg. 222, Q. 377.
 . Ibid, Pg. 204, Q. 141; Ajwabat al-Istiftaat of Ayatolah Khamenei, Pg. 27, Q. 141; Istiftaat (Bahjat), Vol. 1, Pg. 233, Q. 837.