Is liquid Vaseline oil and other oils applied to the body and hair considered a barrier preventing the water of ablution from reaching the skin, due to the sensation of something solid upon contact with water, or are these merely whispers (waswas)? If they are a barrier, what hair oil is not an insulator against water? And does Fairy dish soap contain alcohol, and what type of soap does not raise suspicions about containing alcohol?

Oils and fats that form an insulating layer preventing water from reaching the skin invalidate tahara (purification), such as Vaseline or Brylcreem if applied excessively to a part of the body; their physical substance must be removed. As for oils that do not prevent water from reaching the skin, such as olive oil and sesame oil, they do not affect tahara.

The basic principle regarding the use of shampoo, soap, and skin cream is permissibility, unless a Muslim becomes certain that it contains a forbidden substance. The soap known as "Fairy" is permissible to use unless it becomes clear that it contains alcohol.