If water is available, is it acceptable to clean oneself (after relieving oneself) with stones (istijmaar) or tissue paper, and if that is acceptable, what is the evidence for that? Which is better, istinja’ (cleaning oneself with water) or istijmaar (cleaning oneself with stones etc)?.


Praise be to Allaah.
 

Istijmaar is valid whether one uses stones or tissue paper,
even if water is available; there is no difference of opinion among the
scholars on this point. 

The evidence that istimaar using stones and the like is
acceptable is the report narrated by al-Bukhaari (159) and Muslim (237) from
Abu Hurayrah (may Allaah be pleased with him), which says that the Messenger
of Allaah (peace and blessings of Allaah be upon him) said: “Whoever
does wudoo’, let him rinse his nose, and whoever does istijmaar let him use
an odd number.” 

Ibn al-Qayyim (may Allaah have mercy on him) said in
Ighaathat al-Lahfaan (1/151) that there is consensus among the Muslims
that it is permissible to do istijmaar using stones both in the winter and
in the summer. 

When doing istijmaar using stones, it is stipulated that one
should wipe three times or more in order to clean the place properly. That
is because Muslim (262) narrated that Salmaan al-Faarisi (may Allaah be
pleased with him) said: “The Prophet (peace and blessings of Allaah be
upon him) forbade us to clean ourselves using less than three stones.” 

Doing istinja’ with water is better, because of the report
narrated by Muslim (271) and al-Nasaa’i (45) from Anas ibn Maalik (may
Allaah be pleased with him) who said: When I was a boy, when the Messenger
of Allaah (peace and blessings of Allaah be upon him) entered the
toilet I would carry a small vessel of leather filled with water, and he
would clean himself with water.  

Ibn Qudaamah (may Allaah have mercy on him) said in
al-Mughni (1/206): 

If a person wants to do
just one of them, then using water is better, because of the hadeeth that we
have narrated, and because it purifies the place and removes the dirt itself
and its traces, and is more cleansing. 

But limiting oneself to stones only is sufficient, and there
is no difference of opinion among the scholars concerning that, because of
the reports that we have mentioned and because that is the consensus of the
Sahaabah (may Allaah be pleased with them). 

And Allaah knows best.