You saw me before I was born. Every day of my life was recorded in your book. Every moment was laid out before a single day had passed. ~ Psalm 139:16 (NLT)
For in him we live and move and exist... ~ Acts 17:28a (NLT)
The "you" and the "him" are the Lord. And the point of both passages is that he is the source behind who we are and what we become. He's got a plan that he is creatively working out through our lives. And the point is that it's not all pointless. We are not the product of randomly generated circumstances.
This doesn't necessarily mean that God generates all circumstances -- no, at least not directly. But there is nothing that he can't use to carry out the plan spelled out in "his book." And if we acknowledge with Paul in Acts 17 that "in him we live and move and exist..." we can relax in the the purposefulness of God.
In Acts 17 Paul is addressing the religious philosophers of Athens who had constructed idols ad nauseam just to make sure that they had covered their butts and had left no god unappeased. There is a kind of slavery that we experience when bad things happen and we pour our energy into trying to make sense of it all -- and to preventing it from happening again. I'm not talking about common sense, such as knowing that we can prevent colds by washing our hands. I'm talking about a kind of superstition -- whether appeasing the ancestors in Asian cultures so they don't come back and cause problems or in the West wearing a special cross or religious medal because we think they somehow ward off evil spirits. We spend a lot of time and energy working the system.
We don't have to get sucked into that mode of living because God is the source of life and all that happens fits into his plan. We can relax in this knowledge.
Lord of the universe, help me to trust you and to relax in the fact that you have a plan that you're working out and that all that happens to me is by your hand easily incorporated into that plan. Save me from worry, frenzy, and supersition so that I can more fully witness to your faithfulness. Amen.