TAUNTON, Mass. – Jacques Robidoux recognized the signs that his infant son was starving: He heard the pained cries. He saw him grinding his baby teeth. He felt his tiny bones when he bathed him.

Yet Robidoux, a leader of a religious sect, maintained God had told him and his family to stop feeding the baby solid food. The sight of his son’s withering body was just an act of Satan testing their will, he said.

Jurors did not believe him.

Robidoux, 29, was convicted Friday of first-degree murder after he admitted he watched Samuel starve over 51 days without solid food and die on April 26, 1999, three days shy of his first birthday. He showed no emotion as he was sentenced to an automatic life sentence without the possibility of parole.

Robidoux is one of the leaders of a small sect known as “The Body,” a group that rejects modern medicine, government and science.

Prosecutors say Robidoux’s sister, Michelle Mingo, who was also in the sect, concocted the “prophecy” about withholding solid food out of jealousy. She allegedly said God told her that Robidoux’s wife, Karen, needed to overcome her vanity and go on a high-fat diet to gain weight. She also said Karen should take her son off food and give him only her own breast milk.

Prosecutors say the child starved because his mother had become pregnant again and stopped producing enough milk to nourish the boy.

“It was as atrocious an act as you can have when a parent, two parents in this case, kill their child, not in a drug-induced haze, not in a violent rage, but as coldly as one could commit such a horrendous act – day in, day out, for 51 days,” prosecutor Walter Shea said.

Defense attorney Francis O’Boy said the conviction automatically would be appealed under state law. He also said he planned to ask for a new trial.

During the trial, Robidoux choked back tears as he described how his son went from a healthy, 10-month-old boy taking his first steps to a weak, emaciated baby who could no longer crawl.

“His cry wasn’t a normal baby’s cry,” Robidoux said. “He ground his teeth. Towards the end, he would often bite down on Karen’s nipple. At times, his eyes would roll up in the back of his head. His skin on his chest changed to a dark color. He began getting a white, chalky substance in his diaper.”

Karen Robidoux, 26, faces trial Sept. 3 on a second-degree murder charge. Michelle Mingo also faces a trial on an accessory charge.

Jurors rejected the option to convict Jacques Robidoux on a lesser charge.

The defense maintained the child could have died from some other cause but used only two witnesses: Robidoux and a forensic specialist who said he could not determine starvation was the certain cause of death.

In closing arguments, O’Boy urged jurors to recognize that Robidoux acknowledged his mistakes and find him innocent. He noted that the sect did not believe in modern medicine, and he suggested it might have been ignorance on the part of Robidoux that led to the boy’s death.

“Unfortunately, the religious beliefs drilled into him as a youngster clouded his ability to make the right decision,” O’Boy said.

In Robidoux’s journal, which prosecutors used as evidence against him, Robidoux repeatedly described his wife’s fears as she watched her once-healthy son become emaciated.

“As the day grew on, Satan used the physical sight of Samuel to really get to her. He was obviously losing much weight and becoming much weaker,” he wrote on March 14, 1999, seven days after the starvation began.

The sect is made up of about 40 members of two large extended families who lived in communal homes in Attleboro and Seekonk, about 20 miles south of Boston.

Former members testified that they thought of themselves as “God’s chosen people,” and shunned modern life. Televisions, checkbooks, jewelry and eyeglasses were not allowed. Eventually, group members threw all of their books away, except for the Bible.

Robidoux acknowledged at the trial he never sought medical attention for his son. Instead, he, his wife and other members of the group prayed for Samuel.

Robidoux said he did not think Samuel would die. He said he believed God would perform a miracle – through him – to save the boy.

Another sect member, David Corneau, led authorities to Samuel’s body. His remains were found buried next to the remains of his infant cousin, Jeremiah, in Baxter State Park in Maine.

Corneau received immunity in exchange for his testimony against Robidoux.

Corneau and his wife, Rebecca, were not charged in the death of their son, Jeremiah. They said the boy was stillborn.