Tony Abbott's message was a shot across the bow for Malcolm Turnbull.
"It's obviously a dramatic loss of discipline inside the government and it's a serious attack on the authority of the leadership."
The former prime minister was talking about a move by a small group of Liberal MPs to bring on a private member's bill to allow same-sex marriage.
But behind the message lay a blunt warning - Turnbull must stick with the promise of a plebiscite which was taken to the 2016 election or face a continuing cold war with conservatives.
The worst aspect of it is that in promising a plebiscite, Abbott strapped a bomb to Turnbull's leg.
Turnbull has long been in favour of same-sex marriage and knows the fastest and most appropriate way to deliver it is to allow Liberal MPs a free vote on a well-constructed, multi-party bill in parliament.
Out of 22 countries which now allow same-sex marriage, only Ireland put it to a popular vote - which was successful.
All the rest passed legislation or were compelled through court challenges to act.
However, the prime minister is weighed down by what Queensland Liberal MP Warren Entsch has described as a "captain's pick" by Abbott, who he says deliberately "ambushed" Liberal supporters of same-sex marriage by calling together a controversial joint coalition party room meeting in August 2015.
"He (Abbott) saw this as a means of delaying this even further," Entsch said on Sky News on Thursday.
The plebiscite had become "almost impossible to sell" to the electorate and was undermined by the fact it was not binding and some coalition MPs had said they would not honour or support a "yes" outcome, Entsch added.
With the issue having been "debated to death", Entsch argues it's time to have the parliamentary vote.
The prime minister has agreed for the Liberal Party room to discuss the issue when it next meets in Canberra on Tuesday, after the long winter break.
That meeting is expected to weigh up several options - potentially even voting on the options in a secret ballot.
Turnbull could recommit the plebiscite bill to parliament, seeking to win over the Nick Xenophon Team which opposed the initial bill.
That would honour the coalition's election commitment, be acceptable to conservatives, send a clear message to voters and reassert the prime minister's authority.
At least for a while.
A second option could be to recommit the bill, but under the clear proviso that if it does not pass, the government will hold a voluntary postal vote - effectively a national opinion poll - and act on its outcome in parliament.
This could provide some leverage in convincing the crossbench to support the compulsory plebiscite.
There is a risk the first two options could force the hand of the handful of Liberals seeking a parliamentary vote and they could cross the floor to bring on the bill for a vote - a suspension motion requiring 76 votes - and then vote for the bill.
This is the point at which Abbott and colleagues say Turnbull's leadership would be threatened, because it would show the government has lost control of the numbers in the lower house - in other words, a de facto no confidence motion.
Promoters of the private member's bill say this is is rubbish, pointing to many instances of coalition members crossing the floor and a number of lost procedural motions.
However, they underestimate the depth of feeling among conservatives that moderates, led by Turnbull, are undermining the coalition's voter base and forcing supporters into the hands of parties such as One Nation and the Australian Conservatives.
A third option would be to recommit the bill under the proviso that if it does not pass this term, Liberal MPs would be guaranteed a free vote in the next term of government.
Pro-reformers could argue it merely delays the inevitable, so why not bring it on now?
But it has the added advantage of sticking by the 2016 election promise while putting Turnbull's stamp on a new policy.
It would also mean whoever wins government, Australia would have same-sex marriage in the next term.
Unless, of course, there is a change of Liberal leadership before the next election.