Is it permissible to say "Bismillah" before ablution in the bathroom, and is it permissible to say it in one's heart if the place of ablution is attached to the bathroom, in order to avoid uttering the name of Allah aloud therein?

It is disliked to mention Allah in the place of relieving oneself, out of reverence for the name of Allah. This is based on what Muslim narrated from Ibn Umar, that the Prophet, peace and blessings be upon him, did not return the greeting of peace while he was urinating, and the hadith of Al-Muhajir bin Qunfudh: "I disliked to mention Allah, the Almighty and Majestic, except in a state of purity."

If the place of ablution (wudu) is inside the restroom, scholars differed: 1. Some held the view that one should say "Bismillah" (in the name of Allah) in the heart without uttering it. 2. Others held the view that one may pronounce it verbally, and there is no dislike in doing so. This is because they prioritized the permissibility of saying "Bismillah," which is obligatory or highly emphasized, and dislike is removed when there is a need, as stated by Sheikh Ibn Baz and the Permanent Committee.

However, if the place of ablution is outside the restroom, then uttering "Bismillah" verbally is permissible and there is no dislike.