Police have launched murder investigation after a 64-year-old man was found dead at his home in Crumlin, Co Antrim on Sunday evening.
Mr Flowerday, 64, was last seen alive leaving Dundrod Presbyterian Church on his bicycle on Sunday afternoon.
His body was discovered at his Mill Road home later that evening.
Police have appealed for anyone who saw Mr Flowerday between 12.45pm and 9.50pm on Sunday to contact them.
Until recently, the keen cyclist taught Maths at Antrim Grammar School where he was highly regarded as a caring and supportive member of staff.
In a Facebook message on Monday night, a former pupil of Mr Flowerday said: “I’m so heartbroken and devastated. Thank you for how you encouraged me in the past Robert.”
Mr Flowerday also privately tutored the children of one woman who posted her own tribute, saying: “Absolutely devastated to hear of the death of Mr Robert Flowerday. He was truly a gentleman. I cannot believe that anyone would want to hurt such a kind and genuine soul. RIP Robert. Our loss will be heaven’s gain.”
One message posted on the Rate My Teacher website last year praised the teacher for his helpful attitude.
“Mr Flowerday is an extremely helpful teacher. I cannot rate him too highly. I know of several students who echo my sentiments,” the pupil said.
Police and forensic experts spent Sunday evening and all day yesterday at the scene.
DCI Alan Dickson added: “I am particularly keen to speak with anyone who saw or spoke with him at any time over the weekend, or anyone who was in his company. If you have any information that can assist us with our inquiries, contact detectives on the non-emergency number 101, quoting reference number 1304 28/01/18.”
UUP councillor Paul Michael said there was a “sense of shock and horror” in the community at the news.
“It’s shocking when you have anyone elderly living on their own found dead on their property
“He had lived their for a quite a number of years and was always pleasant to everyone, so the situation is one of shock and horror.
“People are now looking for answers. He certainly didn’t deserve this,” Cllr Michael told the News Letter.
Police said they were called to the scene after concerns were raised by a member of the public and discovered the body of Mr Flowerday inside the house.
DCI Dickson said: He left church on his bicycle to cycle home to Crumlin and he was wearing a high viz jacket.
“I am appealing to anyone who may have seen Mr Flowerday between 12.45pm and 9.50pm on Sunday, January 28 to come forward and speak to police.”
Sinn Fein MLA Declan Kearney has urged anyone with information to contact the police.
“I want to express my own sympathies to the victims family and while details are still emerging of this tragic death I would urge anyone with any bit of information or who saw anything suspicious to bring that to the PSNI,” he said.
Friends and neighbours have been visiting the scene and a number of floral tributes have been left close to the property.