It is possible to know the truth and yet not act on that truth. So knowing God is all-powerful, all-wise, good, loving and sovereign when carefully considered should allow us not to be anxious. Yet knowing these things, we still often are.
Romans 1:16-32 speaks of people suppressing the truth. That everyone because of creation knows enough about God to honour him and give thanks to him, yet they do not. This is the human condition apart from the grace and mercy of God.