Dean of Sydney Phillip Jensen has called on Christians to treat the city's homeless as human beings as the Cathedral prepares for the memorial service for Mitch, the homeless man found dead in the Cathedral Square last week.

Mitch's body was found outside St Andrew's Cathedral School early on the morning of December 6.

Police are refusing to speculate on the cause of his death, but Mitch's friends suggest that he may have been murdered.

Mitch, 23, was known well by many of the Cathedral staff and congregation, particularly Mat Teakle, the Cathedral’s full-time staff worker ministering to the city’s needy.

Mr Teakle will preach at tomorrow’s memorial service.

Writing in the Cathedral Courier, Mr Jensen has called for greater Christian compassion for the homeless.

"The man killed in the square was a person " made in the image of God," Mr Jensen says.

"Somewhere he had a father and mother."

Mr Jensen says that the causes of homelessness are complex and tragic: solving the problem is not as simple as telling people to "pull up their socks' or "get out of bed’.

"All this is our fault as well as theirs," he says. "They may make unwise decisions, but it is our society that has put enormous pressure on people. By the time they reach the streets, the system of our society has beaten them."

Mr Jensen adds that it is not solely "society's' fault.

"The social welfare provisions of our society, both government and voluntary, are enormous," he says. "Yet manifestly there is something wrong when there are many living on the streets in such abject poverty and hopelessness."

He says that Christians and the wider society must stop treating the homeless as "non-persons'.

"He was part of our humanity whom God so loved as to send his one and only Son to die."

"A young man was not killed in our square. Mitch was killed in our square."

The memorial service for Mitch will be held at St Andrew's Cathedral at 2pm on Thursday, December 14.