Augustine of Hippo : In the Decalogue itself it is written, "You shall not bear false witness," in which classification every lie is embraced, for whoever pronounces any statement gives testimony to his own mind. If anyone should argue that not every lie should be called false witness, what will he answer to this statement which is also in the sacred Scriptures: "The mouth that belies, kills the soul"? If anyone should think that this passage can be interpreted to except certain lies, he may read in another passage: "You will destroy all that speak a lie." In this connection, our divine Lord said with his own lips, "Let your speech be 'yes, yes'; 'no, no'; and whatever is more comes from the evil one." Hence the apostle too, when he directs that the old man should be put off, under which term all sins are understood, goes on to explain his remark and specifically says, "Therefore put away lying and speak the truth." — On Lying 5.6 Augustine of Hippo : The law says to you, for example, "You shall not bear false witness." If you know what the truth of the evidence is, you have light in your mind. But if you are overcome by greed for sordid gain and decide in your heart of hearts to bear false witness for the sake of it, then you are already beginning to be tossed about by the storm in the absence of Christ. You are being heaved up and down by the waves of your avarice, you are being endangered by the tempest of your desires, and with Christ apparently absent, you are on the verge of sinking. — SERMON 75.5