The Christian broadcaster, who suddenly lost his wife to leukaemia late last year, said he was praying that the television and radio presenter "pulls through".
Thomas tweeted: "Wishing Richard Bacon every good wish and prayers that he pulls through this. God Bless mate. You're a good man."
Bacon, who co-presented Blue Peter between 1997 and 1998, became unwell while travelling to Britain from America - where he lives - and need to be taken off a plane using a wheelchair.
A spokesman for the 42-year-old said: "Richard remains in a medically induced coma after falling ill last week but he is improving all the time and everyone is hopeful that he will recover quickly thanks to the incredible NHS treatment he is receiving.
Wishing @richardpbacon every good wish and prayers that he pulls through this. God Bless mate. You're a good man.
— Simon Thomas (@SimonThomasSky) July 13, 2018
"This has been very difficult for everyone who loves Richard, all of whom appreciate the many messages of support which have been received, and there will be no further comment at this time."
Chief executive of the Church Army Mark Russell and editor of the UnHerd media platform Tim Montgomerie also tweeted to say they're praying for Bacon.
Bacon's mother, Christine Bacon told the Mansfield Chad: "He was having a lot of oxygen ventilation... as well as lots of antibiotics.
"They kept him like that for a week and we hadn't left his side, at one point we really felt we might lose him."
Really shocked to hear about @richardpbacon being in a medically induced coma, and assuring him of my thoughts and prayers for a speedy recovery https://t.co/G80TjCdAix
— Mark Russell (@markrusselluk) July 13, 2018
She told the newspaper: "The doctors have said that he is very distressed and confused after being in a coma for a week... and that we need to keep talking to him and reminding him of where he is.
"There's a long way to go yet, but this is a very positive step and it has eased my mind."
He wouldn't appreciate my prayers but @richardpbacon is still getting them! Hope you'll be better soon mate x
— Tim Montgomerie (@montie) July 13, 2018
According to reports, Bacon said in tweets that his condition appeared to be pneumonia - where tissue in one or both of the lungs becomes inflammed.
Simon Thomas joined Blue Peter in 1999 and co-presented the popular children's programme until 2005.
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