Miracles occur naturally as expressions of love. They are performed by those who temporarily have more for those who temporarily have less.
Some miracles may seem to be of greater magnitude than others. But remember the first principle of the course; there is no order of difficulty in miracles. In reality you are perfectly unaffected by all expressions of lack of love. These can be from yourself and others, from yourself to others, or from others to you. Peace is an attribute in you. You cannot find it outside.