It is evident from various Azali and Baha'i sources that Mirza Yahya Azal occupied a special status in the Babi community, appointed head of the Babi community

It is evident from various Azali and Baha'i sources that Mirza Yahya Azal occupied a special status in the Babi community, which had been bestowed on him by the Bab. From the outset of his mission (1844), the Bab had faced fierce resistance on the part of the Shi'a clergy and the state authorities, with the result that his remaining years, until his martyrdom in 1850, were spent mainly in prison. It was probably for this reason that he appointed a head for the young community. While in prison, he appointed Mirza Yahya Azal as leader of the Babi community, probably in 1849. ['Abdu'l-Baha does not cite the exact date but mentions only that this appointment was made after the death of Muhammad Shah, which occurred in 1848 (A Traveller's Narrative, pp 62f.) Browne states that Mirza Yahya was appointed to this rank in July/August 1849 (Tarikh-i-Jadid, Intro., p. xviii). In a hitherto unpublished article, Momen concludes that the appointment was made towards the end of 1849.] Because of his appointment to this position, Mirza Yahya was highly respected in the Babi community until the 1860s.

(Making The Crooked Straight by Udo Schaefer, Nicola Towfigh, Ulrich Gollmer, p. 631)