Did people not wipe beforehand?
While I appreciate /u/scarlet_sage’s FAQ link the answers in the FAQ seem to have a significant omission.
[puts on Morpheus voice] What if I told you...that many societies today still don’t use toilet paper?
[Concludes Morpheus voice, as that’s more than enough humor for this sub for now.]
Many cultures historically and around the world are not wiping cultures. They are washing cultures. This is true of virtually the entirety of the Middle East, at least historically and in some areas still today, and as far as I’m aware is also true in much of South Asia (i.e. India.)
The logistics of this vary. Squat toilets remain common in impoverished or more rural/traditional/less Western areas across the region but even in homes or public bathrooms with Western-style sit toilets, a bidet hose, known in Arabic as “shattaf” is universal.
Hand washing is also common in areas without shattaf or a bidet. For those lacking access to running water this might be done with soap and by hand in a river or in the ocean.
Many of the specifically Islamic practices around toilet hygiene are laid out in the Hadith, but are at this point arguably more cultural than religious, for example, you will still find shattaf and not necessarily find toilet paper in an Arab Christian home.
Cultural misconceptions about these practices are also universal. People from wiping cultures tend to find washing cultures disgusting and vice versa. It’s a long-standing Arab trope and part of Middle Eastern culture generally that lack of shattaf or of Hamams (in English, a Turkish public bathhouse), is practically uncivilized.
Mentioning previous discussions is not intended to discourage questions -- further questions, information, and debate is more than welcome.
There is an FAQ section on "Toilet Hygiene" at https://www.reddit.com/r/AskHistorians/wiki/health?v=ef437f02-36aa-11e6-b73f-0e313517c039#wiki_toilet_hygiene . Six of the seven discussions there have to do with wiping buttocks. Edit: NOTE that this is an older version of the FAQ. I can find no references to "toilet paper" or "wiping" in the current FAQ. So I assume that these were considered inadequate answers by current standards and, well, flushed.