What is the ruling on fasting Saturday as a make-up or voluntary fast, and what if it coincides with the Day of Arafah?

It is disliked to single out Saturday for fasting, except for what Allah has made obligatory, due to the Prophet's prohibition of it. The intent of this dislike is to specifically fast on Saturday out of reverence for it, like the Jews. However, it is permissible to fast on Saturday along with another day, or if it coincides with a person's usual fasting habit, or if it coincides with the fasting of a legislated day like the Day of Arafah. There is also no harm in fasting it if it coincides with an obligatory fast, such as making up for Ramadan or an expiation. Some scholars have weakened the hadith that prohibits fasting on Saturday, and according to this view, there is no prohibition against fasting it.