As the former finance minister sought peace in Tuscany, his colleagues rounded on him for betraying the trust of the voters. The left wing, which had stood behind Mr Lafontaine throughout his career, felt especially embittered.
Heide Simonis, Prime Minister of Schleswig-Holstein, accused her erstwhile comrade on the left of "letting down all those in the party who had supported him through clenched teeth".
"I was horrified at the way Oskar Lafontaine left," declared the MP Helmut Wieczorek, the Social Democrats' defence spokesman. "You can't treat a party which entrusts you with high office this way."
Wilfried Penner, another MP, said a resignation should be a quiet affair and its reasons should be clear. This, he concluded, was not the case with Mr Lafontaine's abrupt departure.
It was still not clear last night whether Chancellor Gerhard Schroder had been able to speak to his disenchanted colleague since last Thursday's resignation, beyond the two words - "not now" - reportedly uttered by Mr Lafontaine on the telephone. Mr Schroder had confessed to a hoaxer, a broadcaster pretending to be President Roman Herzog, that he had not been told of the reasons for the resignation.
As Mr Schroder kept silent, Werner Muller, the Economics Minister, signalled a change in policy by announcing tax reform plans aimed at creating jobs."The tax reform of 2000 will be a signal for an upswing and investment by business," he told Focus magazine.
Meanwhile, Heiner Flassbeck and Claus Noe, left wingers brought by Mr Lafontaine to the Finance Ministry, were reportedly on their way out, marking the end of Mr Lafontaine's Keynesian experiment.