Similarly...

Similarly, it becomes clear that the outer cleanliness, the outside Wudu' , is the act of worship, and of obeying the Lord. Therefore, the purification of the outside results in the purification of the inside, and purging the exterior leads to the purity of the interior.

Generally, the traveler to Allah must, at the time of Wudu' be aware of his being about to stand in the Presence of Allah, the Almighty, as with such states of heart as he has, he does not deserve to be in His Presence, or he may even be dismissed from the Presence of the Lord, the Most High.

Thus, he must get ready to have his outer purification transferred to his interior, and to purify his heart which is the object of Allah's attention, or, actually, is the lodging of His Sanctity from all that is other than Allah, and to take out from his head any notion of arrogance and Oneness, which is the origin of the origins of the impurities, so as to become worthy of His Presence. After that, Imām ar-Ridā (' a ) explains the reason for specifying certain organs to Wudu' .

He says: “Confining it only to the face, the two hands, the head and the two feet, was because when the servant stands before the All-Powerful, the parts which are exposed are those which are ordered to be washed in the Wudu' : as with his face he performs the sujūd (prostration), with his hands he requests, desires, dreads and supplicates, with his head he inclines to Him in his rukū' (bowing down) and his sujūd , and with his legs he stands and sits…” The gist of his discourse is that these organs take part in worshipping Allah, and it is through these organs that worship is manifested.

Consequently, it is necessary to purify them. Then he refers to those acts of worship which appear from them, opening the way of their being valid and useful to the deserving people, and making the people of knowledge familiar with these secrets that the organs on which servitude appears in Allah's Blessed Presence, should be clean and purified, as the outer limbs and organs of the body, which have a deficient share of those meanings, would not be worthy of that station without purification.

Although submission is not, actually, a character of the face, and none of requesting, desiring, dreading, supplicating and facing the qiblah belongs to any of the tangible organs, yet, as these organs are the manifestations of those meanings, they must be purified.