It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that once the Prophet (peace and blessings be upon him) addressed us and said, "O people! Hajj has been made obligatory upon you." Upon hearing this, Aqra' bin Habis stood up and said, "O Messenger of Allah! Is Hajj obligatory every year?" The Prophet (peace and blessings be upon him) said, "If I had said yes, it would have become obligatory upon you every year, but if that had happened, you would not have been able to do it. Hajj is obligatory once in a lifetime, and whatever is more than that will be voluntary Hajj."