NUJ Irish secretary Séamus Dooley will write to Paisley following publication of his 750-word Facebook response to McBride’s news analysis piece on the likelihood of abortion being legalised in Northern Ireland.
Séamus Dooley said: "Sam McBride outlined the current political context in Northern Ireland. As an experienced political analysist, he set out the facts and placed them in the context of the current political situation in the UK. At no stage has he expressed a personal opinion on the substantive subject of abortion.
"Ian Paisley’s consequent attack on Sam McBride was unwarranted and unworthy of an MP. It was a clear attempt to smear the professional reputation of a conscientious journalist. The tone and tenor of Paisley’s comments were unacceptable and completely misrepresent the position of McBride.
"Paisley is not entitled to impute political motives to the political editor of the News Letter in a manner which is designed to undermine his professional reputation.
"Paisley has gone beyond the bounds of acceptable political discourse and has engaged in a deeply personal attack which is extremely damaging. His references to McBride’s family background, religion and education were inappropriate.
"The consequence of this behaviour has been a vile reaction on social media. In considering Paisley’s comment I hope the DUP leadership and members will recognise the integrity of McBride and his track record as a journalist of long standing."