It's both an honour and a cruel irony.
Belanger is no longer able to speak at all, due to the ravages of amyotrophic lateral sclerosis, commonly known as Lou Gehrig's disease.
Liberal MP Mauril Belanger answers a question during question period in the House of Commons in December, 2015. (Photo: The Canadian Press)
It is an incurable, progressive, neurodegenerative disease that causes muscle weakness, paralysis, and eventually, respiratory failure.
He'll carry out his Speaker duties with the aid of a tablet computer, which converts pre-programmed text to audio.
Belanger had been considered a front-runner for the post of Speaker last fall but he was forced to withdraw from the race after being diagnosed with ALS in late November.
House set to honour veteran MP
MPs from all parties subsequently unanimously passed a motion to appoint Belanger honorary Speaker for a day, as a way to record their deep appreciation of his "distinguished and faithful service to Parliament and to Canada."
The Ottawa MP's condition has deteriorated rapidly since that motion was passed in December so his day as Speaker on Wednesday will turn out to be only about an hour.
He is to participate in the daily briefing Speaker Geoff Regan receives from Commons clerks and will then take part, with the help of a walker, in the Speaker's parade into the Commons.
He will take the Speaker's chair and preside over the daily prayer, the singing of O Canada, member's statements and the first 20 minutes or so of question period before handing the reins back to Regan.
"Receiving such an honour is highly appreciated since this is a dream coming true amidst the health challenges which I am facing."
"Receiving such an honour is highly appreciated since this is a dream coming true amidst the health challenges which I am facing," Belanger said in a written response to questions.
Just last week, Belanger travelled to Namibia and South Africa as part of delegation from the Canada-Africa parliamentary association, which he co-founded.
His chief of staff, Alexandre Mattard-Michaud, said Belanger is determined to continue serving as an MP until he is no longer physically able to do so. How long that will be is impossible to say since some ALS sufferers deteriorate quickly and then plateau for several years.
For now though, Mattard-Michaud said Belanger believes he has a duty to continue representing his constituents, which he considers to be an MP's primary responsibility.
"Through my daily efforts and the efforts of my personnel, we have provided assistance to more than 10,000 people living in Ottawa-Vanier with cases such as immigration, taxes, citizenship, work, housing, pensions, among other things," Belanger said.
"This is what I am most proud of."
ALSO ON HUFFPOST: