Weeks before he killed his ex-girlfriend at a secluded SEPTA station parking lot in Abington, a Fox Chase teen told his mother his plan.

“I’m really going to kill her,” Gilbert Newton III, 19, texted his mother, Judy, after seeing a picture Morgan McCaffery had posted on social media with her new boyfriend. “I’m gonna stab her in the neck 57 times.”

Later that month, prosecutors say, Newton slashed and stabbed McCaffery at least 30 times, leaving her to die alone on the gravel. The fatal attack came as McCaffery, 18, a recent graduate of Nazareth Academy, met with Newton at the Meadowbrook train station on July 27, 2020, at his request for one final conversation after their breakup.

On Tuesday, jurors in Newton’s trial for first-degree murder in McCaffery’s death were told of his prescient words to his mother and were also given a detailed record of the many heated text conversations with McCaffery in the weeks before her death.

The texts elicited little reaction from jurors or Newton, who hung his head quietly as they were read by a county detective. At one point, Newton’s grandmother was unable to stop sobbing and had to be escorted out of the courtroom.

In one message, Newton told McCaffery to keep her “head on a swivel,” because he was going to stab her repeatedly.

Newton took the stand Tuesday in an attempt to explain those messages, saying he had been upset and distraught in the two months since McCaffery ended their yearlong relationship.

He said that he loved McCaffery, that she was the person he “cared for most on this whole entire planet.”

“I understand those text messages don’t make sense,” Newton said. “I was upset. I said things I didn’t mean.”

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Newton and his attorney, A. Charles Peruto Jr., concede that he was responsible for McCaffery’s death. But they said he went to the meeting at the train station planning to kill himself, bringing along two kitchen knives he had stolen from his mother.

Things changed, Newton said, when McCaffery mocked him and then slapped him after he called her a derogatory name. After that, Newton said he turned the knives on her in a burst of anger.

“I had so much running through my mind,” he said. “I was supposed to stab myself, but as soon as she slapped me and spat on me, I thought: ‘She must not care about me.’”

Under questioning from Assistant District Attorney Kathleen McLaughlin, Newton said he did not remember much of the attack on McCaffery. Nor could he explain why he did it.

“I blame no one but myself,” Newton said. “I blame myself completely.”

The trial in Norristown is expected to end Wednesday.