When the Holy Prophet (Sallallahu alaihi wa sallam) took the pledge from the Sahabah, Allah SWT revealed the following verse and declared the Prophet’s hand as His own hand.
“…the Hand of Allah is over their hands…” Surah Fath (48:10)
Hadhrat Yazid bin Aswad (May Allah be well pleased with him) narrates about the hand of the Holy Prophet (Sallallahu alaihi wa sallam) “I had the good fortune of meeting the Holy Prophet (Sallallahu alaihi wa sallam), I found that the His hand was cooler than ice and more fragrant than musk.” (Zurqani ‘al’al mawahib Vol 5, Pg No: 453)
Hadhrat Abu Juhaifah (May Allah be well pleased with him) says, “People would kiss His hands and rub them on their faces to gain blessings. I also took His hand and placed it on my face. I found that it was cooler than ice and more fragrant than musk.” (Sahih Bukhari Vol 1, Pg No: 502)
His hands' miraculous attribute was that wherever He (Sallallahu alaihi wa sallam) would place it, that place would be blessed forever. The blessings of His hand would heal diseases; remove troubles; dry udders of a goat would overflow with milk and streams of water would run forth from His fingers. A wave of His hand would split the moon into 2 and the set sun would return.
Hadhrat Aiz bin Amr (May Allah be well pleased with him) narrates,” In the Battle of Hunayn, an arrow got stuck in my forehead; because of it, blood kept flowing on my head and chest. The Holy Prophet (Sallallahu alaihi wa sallam) wiped the blood off my face and chest with His hands and prayed for me. The blessing of His hand was such that the area He touched became bright and radiant.” (Seerat halbiya Vol 2, Pg No: 128