Araceli Meza, 49, is charged with injury to a child.
Police say an anonymous caller told them the toddler died last month after falling off a chair in Meza's home, which was being used as a church.
According to the affidavit for Meza arrest, witnesses said the child had been forced to fast for more than 20 days and was only given water.
Several of them said they tried to feed him, but were scolded by Meza and the other pastors of the church who believed he was possessed by a demon, the document says.
The affidavit states that "Suspect Meza advised that the fasting ended when victim looked like an alien…that was the sign that the demons were gone."
Documents show that Meza had members of the church, including her husband, the pastor, convinced that she was a prophet receiving orders from God
On March 22, the witnesses said they saw the boy sitting at a table in the kitchen. He dropped his crayons and then fell and hit his head several times.
The document says there was a religious ceremony performed on the boy to try to resurrect him. Ultimately his body was wrapped in a blanket and taken by his parents to Mexico.
Police still have not found the boy's body.
The affidavit says Meza is charged because as one of the leaders of the church, she was responsible for denying the boy food and proper medical care.
She told investigators she didn't want to do it, but that God had spoken to her directly. If the boy "acted up or would not say ‘Amen' during feeding, [he] would be denied food," she said during an interview.
Meza is being held in the Balch Springs jail on a 100,000 bond.
Police do expect more arrests.
SMU theologian Philip Wingeier-Rayo studies Mexican-American faiths.
"This is a group of people that believes literally in spiritual warfare, and that the world around us is filled with demons and when you have a problem or a situation, you have to confront that by spiritual means," said Philip Wingeier-Rayo.
At a makeshift stage at a nearby property that the Mezas own, a cross still hangs on the back wall, indicating they may have, at some point, used it for services.
Police say the child's parents are also considered suspects and could face charges if they are located or try to return from Mexico.
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