He is the imam of the Shi'a Buratha Mosque in Baghdad.
In March 2005 he condemned the government of Jordan after a suicide bombing blamed on a Jordanian national. He said "all of Jordan is a weapon to be used against Iraq, especially against the Shia".
In April 2006 three suicide bombers killed at least 69 people in an attack at the Buratha Mosque. al-Saghir accused Sunni politicians and clerics of waging "a campaign of distortions and lies against the mosque".
Two months later he was the target of another suicide bomber from al-Qaeda in Iraq, who killed 13 people when he blew himself up in the mosque.
In October 2006 he was one of the senior Iraqi clerics who prepared the Mecca Declaration condemning sectarian violence.
In November 2006 he clashed in Parliament with Sunni Arab leader Adnan al-Dulaimi, which was shown on live television. He claimed Shiites in some areas were enduring violence that was driving them towards militias and "opening the gates of hell", and that Sunni Arab parliamentarians were inciting the violence.
In February 2007 the Buratha Mosque was searched by Iraqi Special Forces as part of the Baghdad Security Plan after complaints that the mosque was a base for sectarian death squads.