FairMormon is a non-profit organization dedicated to providing well-documented answers to criticisms of LDS doctrine, belief and practice.
Pergunta: Será que alguns líderes da Igreja ensinam que o casamento plural era uma prática que persiste para sempre?
Question: Did some Church leaders teach that plural marriage was a practice that would persist forever?
Heber C. Kimball's remarks make it clear that plural marriage will remain a true principle, but in the same breath he anticipates a time when it will not be required
Jerald and Sandra Tanner wrote that "Brigham Young" said that polygamy would never go away in Deseret News of 7 November 1855. However, the remarks were made by Heber C. Kimball, not Brigham Young. Kimball's remarks make it clear that plural marriage will remain a true principle, but in the same breath he anticipates a time when it will not be required or in force for all those who are saved—which is exactly the opposite impression which the critics wish to create.
The issue of the Deseret News cited has a talk from Heber C. Kimball that addresses polygamy, but not Brigham Young. 
The text reads, in part:
The principle of plurality of wives never will be done away, although some sisters have had revelations that, when this time passes away and they go through the veil, every woman will have a husband to herself.
Heber clearly teaches that the principle "will never be done away," but then readily admits that some of the sisters (who are obviously not fond of the practice) have been reassured that the requirement that they practice it has been revealed to them to be necessary only for this life.
- "Remarks by Heber C. Kimball, directly after the sermon by President B. Young, printed in no. 34: Bowery, Oct. 6, 1855," Deseret News Vol. V, No. 35 (7 November 1855): 274 (2nd page of this number). off-site