Anxiety or the feeling of anxiousness is often experienced by those who are worried about things that would happen. Some refer to this as overthinking while others feel anxious because they think something might happen.
Uncertainty is a normal feeling for a human being because no one knows what would happen in the future. However, this unknown knowledge should not be the source of anxiety. The Bible teaches that we should not think about the problems of tomorrow because the present has enough problems of its own.
Christians should not worry about tomorrow because God is already there, and He would make sure that whatever challenge it holds, we can handle it. Overthinking and anxiety would only lead to poor decisions. God wants us to trust Him more than our fears of what tomorrow would bring.