Mirza 'Ali-Muhammad was born in Mashhad in circa 1850. He was the youngest son of the Hand of the Cause Mulla Sadiq-i-Muqaddas-i-Khurasani, who fought at Shaykh Tabarsi and was tortured with Quddus in Shiraz. Mulla Sadiq-i-Muqaddas was given the title Ismu’llah’u’l-Asdaq by Baha'u’llah, and as his son showed many of his outstanding qualities, Mirza 'Ali-Muhammad became known as Ibn-i-Asdaq, son of Asdaq.
In 1861, while Ibn-i-Asdaq was still a young boy, he was taken by his father to Baghdad to see Baha'u'llah. The visit lasted two years and made a made a deep impression on him. During their stay in Baghdad Baha'u'llah revealed a prayer for Ibn-i-Asdaq:
'I ask Thee, O my God! to give him to drink of the milk of Thy bounty so that he may raise the standards of victory through Me, -a victory which is Thine - and arise to serve Thy Cause, when he groweth up, just as, when a youth, he hath arisen at Thy Command'. 
On his return to Iran Ibn-i-Asdaq and his father were arrested on the orders of the governor of Khurasan. They and two other Babis were chained and taken to Tihran. The intention was to execute them but the government ordered instead that they be imprisoned in the Siyah-Chal. Here they remained, chained together, for 28 months.