In the time of their visitation they will shine forth: Their visitation refers back to 2.20 (see the note there). Just as they thought, God will act (visit them) to vindicate them, although that will happen after death. Then they will shine in triumph (compare Dan 12.3; Matt 13.43). Good News Translation paints the wrong picture here. This is not an occasion of the righteous taking vengeance against the ungodly, but of being vindicated over them, of proving victorious at the end. Shine forth probably has the sense of first coming to light (like a spark emerging from apparently dead ashes) and then coming to glow and give off light (rather than reflecting light). So we may say something like “When God acts to save them, they will start to glow like embers blown to life.”
And will run like sparks through the stubble: This is a familiar figure of judgment. Compare Isa 1.31; Joel 2.5; Zech 12.6; Mal 4.1; and especially Oba 18. The picture is of a grain field that was harvested in the spring. The portion of the plants left standing, the stubble, became dry in the summer heat, and the fields were then set afire. When a spark fell into such dry stubble, tongues of flame went coursing through the field until it was burned. At night flames might still remain, shining in the dark. This is possibly the reference of shine forth in the first line. The “wicked” (Good News Translation) are the burning stubble, the stuff left over after the harvest, but the righteous are not so much blazing out against them in anger (Good News Translation) as sharing in God’s victory over them. The punishment of the wicked is the vindication of the righteous.
An alternative model is:
• When God acts to save them, they will start to glow like embers blown to life, and then blaze up like the fires set by farmers, fires that go racing through the dry fields of stubble.
Quoted with permission from Bullard, Roger A. and Hatton, Howard A. A Handbook on The Wisdom of Solomon. (UBS Helps for Translators). New York: UBS, 2004. For this and other handbooks for translators see here.