And the prayer is three thirds: a third is purification (tuhur), a third is ruku`, and a third is sujud. There is no prayer without tuhur. The wudu is done singly (i.e. the washings are done one time each), and someone who does wudu twice (washing twice), then it is permissible, however he is not rewarded for it. Water, all of it, is pure (tahir) until you know it is impure. Nothing ruins water but that which has a coursing self (i.e. running blood). There is no harm in [performing] wudu with rosewater and doing the ghusl al-janaba with it. As to water which the Sun has warmed, then there is no harm with [performing] wudu with it. It is only disliked [to perform] wudu with it and washing clothing and doing ghusl because it brings about vitiligo. Nothing makes water which is of the quantity of a kurr najis, and the kurr is one thousand two hundred rotl by [the measure of] the Iraqi rotl. It is narrated that the kurr is that which is three hand spans in length and three hand spans in width and three hand spans in depth. Well water is a purifier, all of it, so long as nothing falls into making it najis. Seawater is a purifier, all of it.