Baqiyatullah
The term Baqiya means remainder and the combination Baqiyatullah means the Remainder of Allah. It has a Quranic basis. Literally it means that which is left by Allah. What is meant by this is he is the last personage left for the conveyance of divine guidance. Prophethood was brought to an end and sealed with Prophet Muhammad (pbuh) and now Imamate is going to be brought to an end with Imam Mahdi (pbuh). He is the last individual personification of the divine will and the clearest manifestation of Baqiyatullah. He is more entitled to this title than anyone else and on the day when he will reappear, he will introduce himself with this title. It has been stated that when we want to greet him during the period of occultation it is better to say: Assalamun alayka ya Baqiyatallah fi arzeh. (Peace be upon you, O Remainder of Allah, on His earth.