If you have in your hearts to say… we will not, therefore, be polygamists lest we should fail in obtaining some earthly honor, character and office, etc,-the man that has that in his heart, and will continue to persist in pursuing that policy, will come short of dwelling in the presence of the Father and the Son, in celestial glory. The only men who become Gods, even the Sons of God, are those who enter into polygamy. Others attain unto a glory and may even be permitted to come into the presence of the Father and the Son; but they cannot reign as kings in glory, because they had blessing offered unto them, and they refused to accept them. The Lord gave a revelation through Joseph Smith, His servant; and we have believed and practiced it.
Journal of Discourses 11:269 (Aug. 19, 1866)
Journal of Discourses/Volume 11/Delegate Hooper—Beneficial Effects of Polygamy, etc.