The condemned man had been moved to a rubber-padded holding cell and was eating his last meal when the delay was announced.
The Philippines abolished the death penalty in 1987, but restored it in 1994 because of a resurgence in crime.
The reprieve was granted because the Philippines Congress is due to reconsider its stand on the death penalty. By a majority of eight to five the judges decided that in such circumstances it was unreasonable to carry out the execution.
On Sunday the authorities had barricaded the jail in the capital, Manila. Rival groups of supporters and opponents of the death penalty gathered for sombre demonstrations and prayer meetings.
While he has been on death row, Echegaray has married Zenaida Javier, two years his junior. She vowed to commit suicide if her husband of one month was executed. He pleaded for her to be allowed to hold his hand while the injection was administered.
Filipino film-makers have been queuing up to buy rights to the Echegaray story. The new Mrs Echegaray denies any interest in profiting from this.
Echegaray's story is a gruesome one. His former wife left him when he started having an affair with a neighbour. She then remarried but later returned to Echegaray with a daughter known as "Baby", conceived while living with her second husband. Echegaray was found guilty of raping Baby when she was just 10 years old. She now lives with a foster family and wants her former stepfather put to death. "I feel hurt every time I hear things about me," she told reporters.
The Filipino President, Joseph Estrada, a former film star who often played the role of avenging hero to the poor, had supported the execution. He had told Baby he would not grant clemency.
At the weekend President Estrada explained his decision to back the execution by quoting the 13th-century theologian St Thomas Aquinas: "Although it be evil to kill a man so long as he preserves his dignity, yet it may be good to kill a man who has sinned even as it is to kill a beast".
The powerful Catholic church has provided the main opposition to capital punishment in the Philippines.
The reprieve for Echegaray was greeted by emotional scenes outside the jail but with disappointment from the President's office.
Jerry Barican, his spokesman, said: "What should be done is to enforce the [execution] as quickly as possible. It [clemency] may send the wrong signal to persons committing crimes."
President Estrada appeared at a news conference with Baby, now 15 years old. "Evil has its time, but the good will always have their day," he said.Reuse content