Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates that a man came to the Messenger of Allah (peace and blessings be upon him) and said: O Messenger of Allah! Is Hajj obligatory every year? He replied: No, rather it is obligatory only once (in a lifetime), and after that, whoever wishes to perform voluntary Hajj may do so. If I had said that Hajj is obligatory every year, then it would have become obligatory every year.