Opponents of the Socialist government's 2013 same-sex marriage law were among the first to react to extracts from Sarkozy's book La France pour la vie (France for Life), published in the right-wing paper Le Figaro on Friday.
They were shocked by his declaration that he would not repeal it, they declared, accusing the former president of "hiding behind the politically correct" to execute a U-turn.
In 2014 Sarkozy told an anti-gay marriage group that the law should be redrafted from A to Z and, when he was heckled with cries of "Repeal!", assured them that was more or less what he meant.
In his book he says he has changed his mind and "there will be no question of unmarrying people or going backwards".
Hervé Mariton, an MP for Sarkozy's Republicans who led opposition to the bill when it was going through parliament, accused his leader of "perjury", although current Families Minister Laurence Rossignol was unsurprisingly pleased, pointing out that, despite "an often tense and excessive debate", the majority of French people support the change.
An opinion poll published this month showed only 28 per cent of respondents wanting the law scrapped, down from 37 per cent in December 2013.
In what is being widely styled a mea culpa, Sarkozy admits some errors in style, altough not so much in content, during his presidency.
Maybe it was not becoming for the president to tell a member of the public who took him to task to "Get lost, loser!", he concedes, and perhaps the cruise he took on millionaire corporate raider Vincent Bolloré's yacht shortly after being elected was not such a great idea, given that France was plungeing into economic crisis and the left accused him of being in the pocket of big business.
But on policies his main fault was not to go far enough, Sarkozy says.
He should have scrapped the ISF wealth tax and the 35-hour working week altogether, instead of just watering them down, he says - "The Socialists want fewer rich people, I want fewer poor people."
On immigration and law and order he was ahead of his time, the ex-president claims.
He raised the idea of stripping dual nationals of their French nationality if they were found guilty of criminal acts in 2010 and now President François Hollande wants to put the measure in the constitution for those convicted on terror charges.
And he was accused of copying the far-right Front National on immigration and now the Schengen accord on free movement is breaking down, he says, going on to call for tighter controls and for all social security payments to undocumented migrants to be scrapped and promising a referendum if big changes in policy are not agreed in parliament.