Matthew Amiot, 36, told authorities he walked away from the Sept. 9 blaze because he couldn't extinguish it by spitting on it, prosecutors said. He entered his guilty plea to negligent fire charges in St. Louis County District Court.
The fire destroyed the Adas Israel Synagogue in Duluth, leaving only some charred walls standing and destroying multiple religious artifacts. Construction of the building was completed in 1902.
The synagogue had a congregation of around 75 members, which has dwindled to 40, the Star Tribune of Minneapolis reported. The fire resulted in the loss of $250,000 of religious antiquities and caused $117,000 to the structure.
Eight of the 14 Torah scrolls inside couldn't be saved and a firefighter hit by debris was injured during the blaze.
Authorities don't believe the fire was a hate crime. Amiot said he set fire to some clothes outside the synagogue to keep warm and tried spitting on it when the flames grew out of control.
Prosecutors are recommending probation but plan to ask for a stayed sentenced, meaning Amiot would be sparred additional jail time if he stays out of trouble. He will have to remain in a homeless shelter until his next hearing.
"No fires, no trouble, no nothing,” Judge Shaun Floerke told Amiot.
Tuesday's hearing was moved up from its original October date so Amiot could appear at a housing meeting. He said he's been waiting three years for housing assistance.
He is scheduled to be sentenced Oct. 25.