The text, sent to Ms Spence at 9.18am on April 14, 2011, was read out as financial adviser Tony Kelly gave evidence for a third day at the High Court in Glasgow.
Colin Coats, 42, David Parker, 38, Paul Smith, 47, and Philip Wade, 42, deny abducting, torturing and murdering Ms Spence at a flat at Meadowfoot Road, West Kilbride, between April 14 and 28, 2011.
Cross-examining Mr Kelly, defence counsel Derek Ogg, QC, read out a text which was sent to her from Crown witness John Glen's phone on the day she disappeared.
It read: "Listen stupid, be warned school fees paid today 10, yesterday 10 , 0 down.
"He will chop you up Lynda at 2pm today if that 20 isn't there cash.
"I will help him sort you as he says it's my responsibility as I brought him in. If you don't show, no problem. I will sort things myself."
Mr Ogg said to Mr Kelly: "That is a reference that if sums of money are not paid by 2pm he is willing to chop her up and John Glen will assist him."
Mr Kelly replied: "That's what it says."
The QC also read out another text which was sent from Mr Glen's phone on October 4, 2010.
In part the text read: "Lynda if you don't wisen up - someone is dragging you out of bed and cutting off your fingers."
Mr Kelly was asked about these texts and said Ms Spence had told him she was receiving threats from Mr Glen.
Mr Kelly said: "She was consistently under threat from John Glen for several months.
"She said to me at one time she's been threatened by John Glen and that she would be chopped up."
The financial adviser denied being involved with Ms Spence in a multimillion- pound fraud and said he did not realise that Government of Denmark bearer bonds in the sum of £3.2m and £3.6m were fakes.
Printer Amash Shah Syed, 50, told the court Ms Spence, who was very friendly with his wife, came to his home in late summer or autumn 2010 and asked him to make the bonds as a prank.
Mr Syed told Solicitor General Lesley Thomson, QC, prosecuting: "She said she just wanted it as a prank. For a small amount. Then she asked for some more zeros to be added and she was laughing.
Ms Thomson asked what sort of prank and Mr Syed said: "I think she just wanted to play a prank on someone. We had quite a laugh and joke about it."
He added that Ms Spence went on the internet and asked him to download images to put on the document.
In court he was shown copies of the fake bearer bonds and agreed they were the ones he had made up.
The jury has heard that Ms Spence disappeared on April 14, 2011, and was reported missing by her parents on May 13, 2011.
It is alleged she was tortured and had her kneecaps broken, and a thumb and the tip of a little finger cut off before she was killed and her body was disposed of.
The trial before Lord Pentland continues.