This sage advice comes from Charles Simeon, the great 19th century Anglican evangelical:
1st – To hear as little as possible what is to the prejudice of others.
2nd – To believe nothing of the kind till I am absolutely forced to it.
3rd – Never to drink into the spirit of one who circulates an ill report.
4th – Always to moderate, as far as I can, the unkindness which is expressed towards others.
5th – Always to believe, that if the other side were heard, a very different account would be given of the matter.
From Hugh Evan Hopkins, Charles Simeon of Cambridge (Eerdmans, 1977), p. 134.