Spreading Evil Feelings Causes Great Harm — Eliza R. Snow (August 4, 1842)
The servants of the Lord are required to guard against those things that are calculated to do the most evil— the little foxes spoil the vines — little evils do the most injury to the church If you have evil feelings and speak of them to one another, it has a tendency to do mischief— these things result in those evils which are calculated to cut the throats of the heads of the church.
Nauvoo Relief Society Minute Book, p. 81, The Joseph Smith Papers.