Israel turns back its clocks relatively early each year, for the convenience of Orthodox Jewish prayer schedules.
This year, it seems that the early shift away from summer time may indeed have been blessed. It may explain why Sunday's bombings in northern Israel killed only the perpetrators, and no innocent passers-by. While the clocks went back an hour in Israel last week, they are still set to summer time in the Palestinian West Bank.
Israeli security sources believe that the devices used on Sunday evening were prepared by activists from the radical Hamas Islamic movement in the West Bank, intended as a swift and violent riposte to the Israeli-Palestinian peace accord been signed the night before.
The intention was not to stage suicide bombings, but to have the devices planted in busy areas, and for the bombers to walk safely away before detonation. But, as has now been established, the bombers, unprecedentedly, were not West Bank or Gaza Palestinians, but Israeli Arabs.
The Israeli investigators' theory is that, when the devices were smuggled across, the bomb-makers told the bombers that the detonators had been set for a little after 6 p.m.
Fatally, for the three Israeli Arabs involved, they assumed this meant 6 p.m. Israel time. And so at 5 p.m., Israel time, erroneously believing that they had another hour to get the bombs into position, two of them were still driving a few hundred yards from central Tiberias, and the third was waiting patiently in his car outside Haifa's central bus station.
The bombs went off precisely as the bomb-makers had intended; a deadly hour earlier than the delivery men had expected.
Israeli police and security officials acknowledged yesterday that they had never seriously explored the possibility of bombers, linked to the Hamas extremists, emerging from Israel's 800,000-plus Arab minority.
But they say they now have strong evidence that the bombers were working with Hamas, and had been for some time.
They say that the identity card of one of the dead men, Nazal Kraim, was found five years ago at the site of a Hamas suicide bombing in northern Israel. Kraim had apparently given the identity card to the Palestinian bomber who blew himself up that day, to produce if stopped by police on his way to his mission.
Police arrested two more Israeli Arabs yesterday in connection with the Sunday blasts, bringing the number in custody to seven. Families of the dead men, and many Israeli Arab leaders, have condemned the bombings in the strongest language, but have also highlighted the inequalities faced by the Arab sector as a factor fuelling resentment and anger in the community.
Israel's Jewish leaders, for their part, have been urging the Jewish public not to condemn all their Arab countrymen for the crimes of a handful. Do not "cast aspersions on an entire group of citizens," said the Prime Minister, Mr Ehud Barak.
Mr Barak, meanwhile, yesterday won overwhelming support from his cabinet and in the Knesset for the first phase of the new peace deal, which will see another 7 per cent of the occupied West Bank handed over to Palestinian civilian control by Monday, and 200 prisoners going free today.
The Knesset approved the deal last night in a 54-23 vote, with two abstentions.
Earlier, Mr Barak told the Knesset that the new Sharmal Sheikh accord prepared the ground for a permanent peace deal with the Palestinians, which he hopes to achieve by next September. The Likud opposition leader, Mr Ariel Sharon, denounced the accord as "an opening for endless bloodshed".