A thought is an act but with a difference. A thought is a potent force whereas act is a spent force.
Both will have repercussions that are internal as well as external.
An act may get repeated a limited number of times whereas a thought keeps repeating endlessly. One therefore needs to be more alert regarding what thoughts one harbours.
Since 90% of thoughts are negative in nature, the great significance of positive thought habits.
What is life about?
As stated earlier, one who fails to learn and modify the response accordingly, may undergo repeated life experiences....even life after life. These life events can easily be foretold by occult sciences.
One however takes birth only to learn...to do things differently this time. Learning leads to new thoughts and one may experience something new.
Experiences are supposed to create thoughts of new desires and propel new actions, the cycle continues endlessly...vividly.
For those who follow only a set pattern of thinking, the life cycle continues but pathetically same old way.
Hence the importance of breaking habitual thought processes.
Breaking both such cycles by breaking desires and attaining knowledge regarding self and almighty is subject matter of Spirituality. That may lead to liberation. ?..mukti.