Paul gives a pretty full formula to avoid worry in this passage, mostly from his own life. Being content with what you have, keeping your mind on good things, and finding the peace of God. There is another factor as well: sharing in one another’s troubles. It is one thing to be able to train our own minds not to worry, but it is another to be among people who support and love us, helping us through our tough times. This is one of the greatest purposes of the Church.