Perhaps the first important element of Bacon's essay "Of Truth" is his argument that 

. . . men should love lies; where neither they make for pleasure, as with poets, nor for advantage, as with the merchant; but for the lies sake.

In other words, one of the difficulties in seeking the truth is that men love lying for its own sake because they get some pleasure from lying and do not get the same pleasure from the truth.  More important, according to Bacon, is that "a mixture of a lie doth ever add pleasure," implying that men ultimately prefer a mixture of lies and truth to merely truth, which is simply not as exciting as truth mixed with lies.

Bacon's argument that men prefer lies to truth is set forth clearly in his observation that if one removed from

. . . men's minds, vain opinions, flattering hopes, false valuations . . . and the like . . . it would leave the minds, of a number of men . . . full of melancholy and indisposition, and unpleasing to themselves.

Even though Bacon doesn't argue that all men prefer lies, he is clearly arguing that many men would not be happy without their "vain opinions" and "false valuations."

Bacon ultimately equates the love of truth with being close to God:

The first creature of God . . . was the light of the sense; the last, was the light of reason. . . . 

Because God gave man both sense and reason--and despite the fact that lying gives man pleasure--Bacon concludes that one of the aspects of "heaven upon earth" is simply that men's minds should "turn upon the poles of truth."  

In his last paragraph, Bacon argues that in civil affairs--how men conduct themselves in the daily life of commerce and government--mixing truth and lies is like "alloy in coin of gold and silver, which may make the metal work better, but it embaseth it."  In other words, truth has to be pure, unalloyed with anything that changes its nature.  More important, Bacon makes it clear that there is nothing worse than a man who is known for lying: "There is no vice, that doth cover a man with shame, as to be found false and perfidious."

Lastly, Bacon makes it clear that, at Judgment Day, when Christ appears to judge the goodness or evil of mankind, man's love of falsehood will result in Christ's inability to "find faith upon the earth," a conclusion that can only result in mankind's damnation.