Ablution
الْهِدَايَةُ، الْوُضُوءُ مَرَّةٌ وَ هُوَ غَسْلُ الْوَجْهِ وَ الْيَدَيْنِ وَ مَسْحُ الرَّأْسِ وَ الْقَدَمَيْنِ وَ لَا يَجُوزُ أَنْ يُقَدِّمَ شَيْئاً عَلَى شَيْءٍ يَبْدَأُ بِالْأَوَّلِ فَالْأَوَّلِ كَمَا أَمَرَ اللَّهُ عَزَّ وَ جَلَّ
(The book) ‘Al Hidaya’
‘The Wud’u is once, and it is washing the face and the two hands, and wiping the head, and the feet, and it is not allowed to bring forward anything upon anything, beginning with the first. So, the first is like what Allah-azwj Mighty and Majestic has Commanded.
وَ مَنْ تَوَضَّأَ مَرَّتَيْنِ لَمْ يُؤْجَرْ وَ مَنْ تَوَضَّأَ ثَلَاثاً فَقَدْ أَبْدَعَ وَ مَنْ غَسَلَ الرِّجْلَيْنِ فَقَدْ خَالَفَ الْكِتَابَ وَ السُّنَّةَ وَ لَا يَجُوزُ الْمَسْحُ عَلَى الْعِمَامَةِ وَ الْجَوْرَبِ وَ لَا تَقِيَّةَ فِي ثَلَاثَةِ أَشْيَاءَ فِي شُرْبِ الْمُسْكِرِ وَ الْمَسْحِ عَلَى الْخُفَّيْنِ وَ مُتْعَةِ الْحَجِّ
And the one who washes twice will not be Rewarded, and one who washes thrice, so he has innovated; and the one who washes the leg, he has opposed the Book and the Sunnah; and the wiping is not allowed upon the turban and the socks; and there is no Taqiyyah (dissimulation) in three things – in drinking the intoxicant, and the wiping upon the socks, and Mut’ah of the Hajj.
وَ حَدُّ الْوَجْهِ الَّذِي يَجِبُ أَنْ يُوَضَّأَ مَا دَارَتْ عَلَيْهِ الْوُسْطَى وَ الْإِبْهَامُ وَ حَدُّ الْيَدَيْنِ إِلَى الْمِرْفَقَيْنِ وَ حَدُّ الرَّأْسِ مِقْدَارُ أَرْبَعِ أَصَابِعَ مِنْ مُقَدَّمِهِ وَ الْمَسْحِ عَلَى الرِّجْلَيْنِ إِلَى الْكَعْبَيْنِ
And a limit of the face which is obligated to be washed is what the middle finger and the thumb rotates upon, and a limit of the hands is to the elbows, and a limit of the head is a measurement of four fingers from its front, and the wiping upon the legs is to the heels.
فَإِذَا تَوَضَّأَتِ الْمَرْأَةُ أَلْقَتْ قِنَاعَهَا مِنْ مَوْضِعِ مَسْحِ رَأْسِهَا فِي صَلَاةِ الْغَدَاةِ وَ الْمَغْرِبِ وَ تَمْسَحُ عَلَيْهِ وَ يُجْزِيهَا فِي سَائِرِ الصَّلَوَاتِ أَنْ تُدْخِلَ إِصْبَعَهَا فَتَمْسَحَ عَلَى رَأْسِهَا مِنْ غَيْرِ أَنْ تُلْقِيَ قِنَاعَهَا
When the woman performs Wud’u, she should take off her scarf from place of wiping her head, in the morning Salat and Al-Maghrib, and she should wipe upon it, and it would suffice her for the rest of the Salats to insert her fingers, so she wipes upon her head from without taking off her scarf.
وَ لَا بَأْسَ أَنْ يُصَلِّيَ الرَّجُلُ بِوُضُوءٍ وَاحِدٍ صَلَوَاتِ اللَّيْلِ وَ النَّهَارِ كُلَّهَا مَا لَمْ يُحْدِثْ
And there is no problem with the man praying Salats with one Wud’u, night and day, all of them for as long as he does not break Wud’u’.[1]
[1] Bihar Al-Anwaar V 76 – The Book Cleanliness – Ch 3 H 2 (Chapters on Wud’u)