“Do all things without grumbling or questioning, that you may be blameless and innocent, children of God without blemish in the midst of a crooked and twisted generation, among whom you shine as lights in the world” (v14-15). The ancient world was “crooked and twisted,” yet that didn’t stop God’s people from shining brightly as they did “all things” for His glory. Whatever their circumstances, they could be active, not passive, participants in their own growth and usefulness (v12).
“For it is God who works in you, both to will and to work for his good pleasure” (v13). God can use even difficult situations to bring about His “good pleasure”: our maturity and His glory.