By Ian Dunt
A married life is the best antidote to the "celebrity self-obsessed culture we live in", Iain Duncan Smith will say later.
The work and pensions secretary will tread onto dangerous political ground in a speech which insists that politicians should not be afraid of promoting marriage.
The issue of a volatile one for the coalition, with Conservatives wanting tax cuts for married couples and Liberal Democrats nervous of the paternalistic overtones of commenting on people's relationship status.
"Over the years the political establishment has frowned if a mainstream politician mentions marriage," Mr Duncan Smith will say.
"The prevailing view was that to extol the virtues of this most fundamental institution somehow meant that you were going to stigmatise those who were not married. This is an absurd and damaging assumption.
"Government must understand the effect that family breakdown can have on the well-being of both adults and children."
Marriage is "the best antidote to the celebrity self-obsessed culture we live in" because "it is about understanding that our true value is lastingly expressed through the lives of others we commit to", the former Tory leader continued.
"When asked about their aspirations, young people are very clear that they want to marry. So we have to ask ourselves: if people from the youngest age aspire to make such a commitment in their lives, what stops them doing so?
"Research by the Centre for Social Justice has found that a majority of people out of work or in part-time work think low-earning and unemployed people are better off living apart than as a couple. Only those with money say that money has no bearing on whether people stay together.
"Government cannot and should not try to lecture people or push them on this matter, but it is quite legitimate to ensure people have the opportunity to achieve their aspirations. That is why we are investing £30 million in relationship support and are committed to reducing the couple penalty."
The rhetoric is also likely to raise eyebrows on the other side of the House. Labour leader Ed Miliband has faced repeated questions about his own unmarried relationship with partner Justine Thornton.