He criticized using the phrase "medical assistance in dying" to describe "taking a substance and injecting it into a person, and that makes them die."
"That's not called dying. The word for that is 'killing'. To not know the difference between dying and killing is astonishing."
He warned against euphemisms that are "comfortable and pleasant and sweet, but which do not describe what is happening."
"When we are ashamed, troubled, by what we are doing, I think we always leave the light of clear language. We don't want the light to shine upon what we are doing."
The cardinal said Catholics should strongly encourage palliative care for those in severe pain and for the terminally ill. This, not suicide, is true medical assistance, he maintained.
He said the government also has an obligation to support palliative care if it is going to set up a legal euthanasia regime.
"That's the positive way to deal with this very real issue," he said.
He also stressed the need for conscience safeguards to protect individuals who are "committed to healing, and not to killing."
"They say that there's nothing in the law that somebody must do this. Well, there's nothing in the law. Yet. But this has to be taken care of."
He said individuals and institutions will certainly face pressure to take part in assisted suicide or euthanasia.
"What protections are being offered? There are no protections offered in this bill at all," he said.
Backers of the bill say that Canada's 10 provinces and three territories will provide these protections.
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The cardinal questioned this.
"For all of Canada, they're making it acceptable to provide a noxious substance to somebody. But they're not providing the same nationwide protections for people's consciences and for 'havens of refuge'."
He said that in this "cold world of euthanasia," there must be "places where you know where you will be safe."
He worried of the pressures on the elderly to "hurry up" and die.
"At a time when our priority should be fostering a culture of love, and enhancing resources for those suffering and facing death, assisted suicide leads us down a dark path," he said in an April 14 statement.
He noted that the Hail Mary prayer focuses on "now, and at the hour of our death."