In the October session of General Conference in 1866, Brigham Young made these comments:
“To my certain knowledge, Emma Smith is one of the damnedest liars I know of on this earth; yet there is no good thing I would refuse to do for her, if she would only be a righteous woman; but she will continue in her wickedness. Not six months before the death of Joseph, he called his wife Emma into a secret council, and there he told her the truth, and called upon her to deny it if she could. He told her that the judgments of God would come upon her forthwith if she did not repent. He told her of the time she undertook to poison him, and he told her that she was a child of hell, and literally the most wicked woman on this earth, that there was not one more wicked than she. He told here where she got the poison, and how she put it in a cup of coffee; said he 'You got that poison from so and so, and I drank it, but you could not kill me.' When it entered his stomach he went to the door and threw it off. he spoke to her in that council in a very severe manner, and she never said one word in reply. I have witnesses of this scene all around, who can testify that I am now telling the truth. Twice she undertook to kill him. [Utah Historical Quarterly, vol. 48, Winter 1980, 82] (emphasis added)
If they had popcorn back then, the congregation was just shoveling it in. Can you imagine if one of the General Authorities spoke like that today?
Indeed, Brother Brigham and Emma had a colorful past. From what I understand, the issue between these two was Emma's adamant denial of Joseph's teaching of plural marriage. Brigham didn't take too kindly to anyone contradicting the Prophet; hence the outrage.
The FAIR Wiki does a great job of discussing their relationship in an article titled "Emma Smith and Brigham Young."