The eighth behest is this: ‘Thou shalt say no false witness against thy
fellow-Christian.’
In this behest it is forbidden us that we should lie or forswear
ourselves, either in judgment or out of judgment, in order to cause thy
fellow-Christian harm; and that one should bring none as a witness in
order to impair his (one’s fellow-Christian’s) fame, or his grace that
he hath, for that is deadly sin. Against this behest those act that
slander good men behind them willingly and wrongfully, which one calls
the sin of detraction; and those also that praise the wicked and the
deeds of their wickedness and of their follies, known, or seen, or
heard. That is sin of flattery or of deceit, when one says it before
them; or falsehood or leasings, when he that one speaks of is not
present. For all those are false witnesses.