What is the meaning of hand in Tayammum? Is it only the BACKART of the hand from wrist to the last point of fingers or the WHOLE HAND from wrist to the last point of fingers? If it only means backpart of hand in this case is it needed to wipe space between the fingers? I asked this question before but the answer was not relevent to my question. Plz, answer my questions specifically.

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The hands that should be wiped during Tayammum are the hands, both the palms and the upper part of the hand [i.e., the opposite side of the palm], so the two palms are entirely wiped, including rubbing between the fingers, along with wiping the wrist bone.

Al-Sharh Al-Kabeer reads: “He wipes his face with the insides of his fingers [i.e, with the palms], and the back of his hands to the wrist bone with his palms, and it is desirable to rub one of the palms with the other, but it is not obligatory. Because the obligation of wiping the two palms is waived by passing each one on the back of the palm.”

Kashshaf Al-Qinaa’ reads: “(He wipes his hands to the wrist bone), Allah Says (what means): {and hands} [Quran 5:6], if the mentioning of the hand was absolute, then the arms are not included; for example, cutting off the hands of the thief (if the hands are cut off from the wrist bone, not above it, the place of the cut must be wiped) because some of the obligatory areas (for tayammum) remained as if it was cut off less than the wrist bone.” [End of quote]

Allah knows best.