In time of heat they disappear: the two lines of this verse are parallel, with only a bit more imagery in the second line. In time of heat translates a verb form found only here. In Ezekiel 20.47 another form of the same verb means “scorched.” Here the most probable meaning is “melt”; for example, “When the snow and ice melt, they (the streams) soon disappear.” Disappear translates a word used poetically here, meaning “are made silent.” When it is hot, they vanish from their place: they refers to the stream beds with water, not to the beds themselves. Vanish means the water dries up.

Line b repeats the thought of line a and adds nothing new. Good News Translation has kept both lines and has made line b the consequence of line a. Good News Translation has also linked verse 17 to 16 as a contrast by beginning verse 17 with “but.” In Hebrew it is not a consequence, but rather a step-up of the depiction of the change from warm melting to the heat of the hot season. We may relate verse 17 to 16 as a contrast; however, the more natural relation is that of time sequence. In languages which do not have terms for snow and ice, the translator may say, for example, “When the weather warms, the streams disappear.”

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 .