because when the word “hand” is used without qualification, it refers to the palm. The evidence is the saying of Allah, the Exalted: “As for the male thief and the female thief, cut off their hands.” [al-Ma'idah: 38] What is cut off is only the palm.
When He intended what is beyond the palm, Allah, the Exalted, said: “and your hands up to the elbows.” [al-Ma'idah: 6]
“And whatever it has soiled, and perform wudu, and pour three handfuls of water over his head, enough to soak it, …”
His statement, “and whatever it has soiled,” means that he should wash whatever has been soiled by the traces of janabah. In the hadith of Maimunah, may Allah be pleased with her, the Messenger of Allah, peace and blessings be upon him, while washing what had been soiled, struck the ground or the wall with his hand two or three times (1) …
What appears to me from the hadith of Maimunah is that the water was scarce. This is why he, peace and blessings be upon him, needed to strike the wall with his hand two or three times, so that he could remove what had been soiled more quickly. He also washed his feet in another place.
His statement, “and perform wudu,” means that he performs the wudu for prayer.
The author’s wording indicates that he performs a complete wudu, and this is also stated in the hadith of Aishah, may Allah be pleased with her (2).
His statement, “and pour three handfuls of water over his head,” apparently means that he pours water over the entire head three times.
His statement, “enough to soak it,” means that the water reaches its roots, such that the amount of water is not insufficient.