Where are the hands placed during the sitting between the two prostrations, and how should the right hand be placed over the left, and are there any legitimate postures for that, and what is the meaning of the palm (kaff), forearm (sa'id), wrist (rusgh), arm (dhira'), and elbow (mirfaq)?

Fatwa no. 33935 states that in the sitting posture between the two prostrations, the hands should be placed on the thighs, close to the knees, such that their fingertips align with the knees, and it does not matter if the fingertips are slightly bent over the knees. As for how to place the hands during the standing posture (qiyam), Ibn Hajar Al-Haytami says: "One should grasp the wrist of the left hand with the palm and fingers of the right hand. This (wrist) is the bone adjacent to the thumb and the beginning of the forearm, and part of the wrist joint. The wisdom behind this is to position them over the heart." The 'ku' (كوع - wrist bone) is the third bone connecting the thumb to the wrist. The 'rusgh' (رسغ - wrist) is the joint between the hand and the forearm. The 'dhira'' (ذراع - arm) extends from the elbow to the fingertips. The 'mirfaq' (مرفق - elbow) is the joint where the forearm and upper arm meet. The 'kaff' (كف - palm/hand) is the hand from the wrist to the fingertips.