Sayyiduna Ka'b (may Allah be pleased with him) narrates: "Whoever performs 'Isha prayer after making ablution properly, and then offers four (voluntary) rak'ahs in which he completes the bowings and prostrations, and he knows what he is reciting in them, he will receive the reward of performing these rak'ahs on the Night of Qadr." This narration has been transmitted by 'Ata from Ayman, from Si' Yatabi', and Ayman is the same narrator who reported regarding the Prophet Muhammad (peace be upon him): (In the blessed era of the Prophet, peace be upon him) the price of a shield was one dinar. He belonged to the generation of the Tabi'in; he did not witness the time of the Prophet (peace be upon him) or the caliphs who came after him.