It is narrated from Masruq, he says: We were sitting with Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him), and he was teaching us the Noble Qur'an. During this, a man said to him: Abu Abdur Rahman! Have you ever asked the Messenger of Allah (peace and blessings be upon him) how many caliphs will come in this Ummah? He said: Since I have come to Iraq, no one before you has asked me this question. Yes, we did ask the Messenger of Allah (peace and blessings be upon him) about this, and he (peace and blessings be upon him) said that the number of caliphs in my Ummah will be twelve, which is the same as the number of chiefs among the Children of Israel.