Verse 12 begins Zophar’s portrayal of the ways in which the wicked is paid back for his sins. Verses 12 and 13 describe a condition whose consequences are seen in verse 14. These three verses form one long sentence in Hebrew.

Though wickedness is sweet in his mouth: here the poet depicts the wicked man making the enjoyment of sin last as long as possible and getting out of it everything he can. The imagery is that of a sweet taste in the mouth. In languages in which an abstract quality like wickedness cannot be said to be sweet, it will often be necessary to express the thought in the form of a simile; for example, “Although doing evil things may be like sugar in a person’s mouth…” or “Even though doing evil is like having sugar in his mouth.” In some languages it will not be advisable to have a string of concessive clauses as in verses 12 and 13. These may be expressed as statements.

Though he hides it under his tongue: the purpose of putting the sweet object under the tongue is to make it last and so keep the taste of sweetness lingering in the mouth. This line may be rendered, for example, “even if he keeps the sweetness hidden under his tongue” or “even if he prolongs the sweetness by putting it under his tongue.”

Though he is loath to let it go: verse 13 expresses the purpose of verse 12b, and Good News Translation accordingly reduces these two lines to one, “that he keeps … flavor,” and joins verse 13 with verse 12.

And holds it in his mouth: Bible en français courant has not condensed these lines like Good News Translation, and for translators who are able to preserve them meaningfully, this translation offers a good model:
12 In his mouth evil is sweet like candy,
and he slips it beneath his tongue.
13 He holds it there for a long time, he does not let it go,
prolonging the pleasure of its flavor.

Yet his food is turned in his stomach: the conclusion of this pleasurable savoring of sweetness is that it turns bitter and even poisonous. Turned was used in 19.19, where it referred to “turning against Job.” Here it is used of food that goes bad, becomes sour and indigestible, or, as Good News Translation, “But in his stomach the food turns bitter.” It may be necessary to adjust verse 14a to show how it is linked with verses 12 and 13; for example, “Yet when the sweetness reaches his stomach” or “However, when he swallows the sweetness.”

It is the gall of asps within him: the ancient view was that the gall bladder of snakes secreted poison, and consequently gall of asps means “snake poison.” The word translated asps refers to a poisonous snake, but not exclusively to the asp. Within him is literally “in his intestines.” Good News Translation “as bitter as any poison could be” is somewhat misleading. This line is an excellent example of raising poetic intensity of a general word in line a through the use of a more specific term in line b. In this way his food in line a is bitter in his stomach, but in line b it is more than bitter; it is poison in him. The conclusion of verse 14 may be expressed, for example, “it becomes like snake poison inside him” or “it is as deadly as snake venom in his intestines.”

Quoted with permission from Reyburn, Wiliam. A Handbook on Job. (UBS Helps for Translators). New York: UBS, 1992. For this and other handbooks for translators see here .