For thy strength is the source of righteousness: The connector For may be omitted (see Good News Translation). Source may be translated “beginning.” So translators could say “Your strength is the source [or, beginning] of [your] justice” or “Your justice begins with [or, flows from/arises from] your strength.” The meaning is that God can act justly because he is powerful enough to do so. Contemporary English Version says it well with “You do what is right because you have the strength to do so.”

And thy sovereignty over all causes thee to spare all: The word “Lord” (Good News Translation) is not in the Greek, which has a verb here for sovereignty. All can be understood as “everyone” or “everything,” but we recommend “everyone.” For this line translators might say “When you show mercy, you are showing that you have power over everyone” or “You have power over everyone, and you use it to show mercy [or, be lenient] to them.”

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.