"My flippant attempt at sparking a debate around it was shithouse and I should have done better at explaining things" he posted, along with a picture of Richard Cockerill's famous staredown of the late Norm Hewitt leading the haka in 1997.
Marler's initial post that the haka was "ridiculous" and "should be binned" was heavily slammed by All Black and rugby fans alike, however he offered some context as to why, saying that he "just wanted to see the restrictions lifted to allow for a response without sanction".
He was referring to the rule instituted by World Rugby prior to the 2011 World Cup that restricts teams from advancing over their own 10 metre line while the haka is being performed, one that he himself famously broke prior to England's upset win over the All Blacks in the 2019 sem-final.
Marler also offered thanks for respondents to his post and the "education received on how important the Haka is to the New Zealand culture".
Earlier, All Black coach Scott Robertson was asked about his feelings on the matter at his team naming press conference.
"The haka for us is a custom. It is part of who we are, our DNA. You can welcome somebody, it is for celebrations, for joy, and also for challenge and we use it as a challenge," said Robertson.
"We believe it is a great tradition of rugby, as it is for all Pacific nations," Robertson added. "It honours where they have come from. It is not just about the All Blacks, it is about us as a country. It means a lot to us."
Asked if he felt teams should be able to respond to the challenge on the pitch, Robertson said he believes they should.
"Obviously, it's a respect thing.
"The crowd enjoy it, don't they? It is a special occasion. Some clap, some put a plane over the top. Whatever it is, there is a lot of meaning behind it and it's got to be meaningful and respectful."
Robertson described England's 2019 response as "awesome and respectfully done".
Crowd responses vary worldwide, but Twickenham crowds traditionally try to drown out the haka with a rendition of their "Swing Low, Sweet Chariot" anthem.