The Mahdi is prophesied to be a descendent of Imam Husayn. Other less specific narrations mention descendancy from Lady Fátimih, Prophet Muhammad, and the tribe of Quraysh. In other words, to be a descendant of Imam Husayn is to kill four birds with one stone, so to speak. Let’s take a look at how Mullá Husayn, the first disciple of the Báb, came to recognize the Mahdi in the following narration:
That night, that memorable night, was the eve preceding the fifth day of Jamádiyu’l-Avval, in the year 1260 A.H. It was about an hour after sunset when my youthful Host began to converse with me. “Whom, after Siyyid Kázim,” He asked me, “do you regard as his successor and your leader?” “At the hour of his death,” I replied, “our departed teacher insistently exhorted us to forsake our homes, to scatter far and wide, in quest of the promised Beloved. I have, accordingly, journeyed to Persia, have arisen to accomplish his will, and am still engaged in my quest.” “Has your teacher,” He further enquired, “given you any detailed indications as to the distinguishing features of the promised One?” “Yes,” I replied, “He is of a pure lineage, is of illustrious descent, and of the seed of Fátimih. As to His age, He is more than twenty and less than thirty. He is endowed with innate knowledge. He is of medium height, abstains from smoking, and is free from bodily deficiency.” He paused for a while and then with vibrant voice declared: “Behold, all these signs are manifest in Me!” He then considered each of the above-mentioned signs separately, and conclusively demonstrated that each and all were applicable to His person. (The Dawn-Breakers, pp. 56-57)
Note that one of Mullá Husayn’s first expectations of the Mahdi is to be a siyyid, that is, descendent of Prophet Muhammad. This is not surprising for if you were to asked a Twelver about the distinguishing features of the Mahdi, he or she will undoubtedly mention His pure lineage and illustrious descent.
Now, some critics argue that the family tree found in The Dawn-Breakers, pp. lviii-lx, discredits the genealogical claim of the Báb because not only His father but grandfather, great grandfather, and great great grandfather, all in the paternal side, were called Mirzá, not Siyyid. To respond, my research has found that the title, “Siyyid”, is not used consistently and therefore, its absence does not necessarily mean that a particular individual is not a Siyyid. Here are a few examples:
- M. S. Ali (Khal-i-A’zam) is called a siyyid but his father (M. Muhammad-Husayn) and son (M. Javad) are not.
- M. S. Muhammad (Khal-i-Asghar) is called a siyyid but his father (M. Muhammad-Husayn) and sons are not. Surprisingly, some of his grandsons are called siyyid: S. Aqa and H. M. S. Muhammad.
- There are three brothers (H. S. Mihdi, H. S. Ja’far, and H. S. Husayn) who are all called siyyid but not their father (H. M. Hasan-Ali). Surprisingly enough, only some of their sons are called siyyid.
- Ali has two sons: H. M. S. Hasan (Afnan-i-Kabir) and H. M. Abu’l-Qasim (Saqqa-Khani). Why is Afnan-i-Kabir called a siyyid when neither his father nor all of his sons share this title? Why is S. Muhammad-Husayn (one of Saqqa-Khani’s sons) called a siyyid when once again, neither his father nor any of his sons share this title?
Abbreviations: H (Haji), M (Mirzá), S (Siyyid)
To conclude, absence of evidence is not evidence of absence. Yes, as far as I am aware, there is no family tree tracing the Báb all the way back to Imam Husayn, but His contemporaries including Mullá Husayn did not require this sort of evidence. It was self-evident because the Báb declared in the city of His birth and childhood. In a close-knitted community, especially in the early to mid-1800s, neighbours knew each other very well and even today, such a title is held in high esteem in public. If the Báb lied about his siyyidhood, people could have immediately called Him out, especially when He claimed to be siyyid from both sides of His family!