As acting party leader Harman advised Labour MPs to abstain. But abstentions will allow the Bill to pass.
The Labour party has its roots in fighting for the working classes and protecting the vulnerable of our country but that dates back to a pre NHS period of history when ill health could be a quick path to the poor or work house.
While many believe that the current Tory government would prefer that sort of self-centred society we remain a long way from those days. However with social security lifelines stretched, and in some cases cut, it only takes a little bad, luck, loss of a job, a relationship breakdown or an extended period of ill health to put you on the streets.
Unless you have or are walking a mile in the shoes of a person down on his or her luck or you are facing many daily challenges, you cannot really judge.
Voters need a real alternative to the Tories and in England there are various political alternatives but that division almost guarantees the Tories success.
All eyes are on the four Labour leadership candidates and many will judge them on how they respond Monday to the work and welfare bill
While Labour must adhere to its principles it will not be effective if it cannot secure enough votes in any coming elections.
The mainstream media accuse Labour of losing its credibility and some of the party's supporters do the same.
In trying to please a majority of voters in the UK Labour failed so why not turn further to the left? That view may be fine if you are happy to keep the Tory status quo.
In-fighting has never done the Labour party any favours in the past and it won't in the 21st Century either.
Liz Kendall, Yvette Cooper, Andy Burnham and Jeremy Corbyn are standing for Labour leader and all are Labour representatives.
Attacks on social media including accusations against some Labour MPs of being pink or even red conservatives are silly but also dangerous.
Twitter is awash with trolls right now and there are many wolf in sheep's clothing, or rather right wingers pretending they are not.
Let's face it any person can push an agenda on Twitter whether they believe in it or not.
Jeremy Corbyn, an outsider in the Labour leadership race now a front runner, standing on an anti-austerity mandate is 66 and if he has not made it as leader of the party by now you have to wonder why. In the 2020 election he will be 71.
If you comment on that on Twitter expect a troll to call you ageist but as a 63-year-old female Labour voter I would call it realism.
If those pushing for Labour on Twitter really want to oust the Tories in 2020, if not before, they need to unite, stop infighting, quit bullying and attacking each other and the candidates, leave their egos at the door and get real.
Perhaps in five years’ time if Tory cuts have continued to bite and the EU referendum has played out people may look to return to Labour.
But for every floating or disheartened voter that will swing to Labour if Corbyn is elected there may be at least one other who will turn away from the party.
Andy Burnham has said he will abstain in the vote on the work and welfare bill Monday
For that some of Corbyn's fans will castigate him. But rebelling against the party whip needs careful consideration. Those who love to see the Labour party in dissaray must be having a field day.
Burnam said he would follow the party whip rather than rebelling but along with others tabelled amendments to the Bill.
If there are enough abstentions it will be enough to smash the bill but the surest way is to vote against it.
For the social media trolls and some political activists it will not be enough.
What that means is unclear. It does however indicate that the bill failing is not as important to some as the message Labour sends to the Tories.
But that message will make some of the electorate run in fear from Labour.
British politics is a complicated affair.
True Labour supporters will get behind whoever is elected, except maybe Liz Kendall.
Labour has five years to formulate a plan for office with the best leader for the job in place but in fighting and squabbles could help the Tories to a 2020 victory.
The WWB debate in the Commons continues-check back later for the result of the vote.
The Government won the second reading of the Conservatives' new welfare bill by 308 to 124; the package, includes cuts to tax credits, reductions in the welfare cap and introduces a "national living wage".
48 Labour MPs rebelled and voted against the bill. These were:
Hannah Bardell, the SNP welfare spokeswoman said " The Tories’ cruel welfare cuts damage the working poor and vulnerable people, and had to be opposed. “Labour had the perfect opportunity to join the SNP in a progressive coalition to oppose the Tories - but with some honourable exceptions they sat on their hands."
Labour tabelled an amendment seeking to derail the legislation but that was defeated by 308 votes to 208.
Labour MPs that toed the party line set by Harriet Harman will now feel the wrath of sections of the electorate.
In an effort to become an electable party Labour have lost some long-standing supporters. Some will stick around if Corbyn is elected party leader; some will look elsewhere and a some may even look at forming a new political party.
All of that of course will leave the Tories laughing all the way to the 2020 election.
A divided electorate suits the Conservatives.