Stand firm against evil thoughts

Stand firm against evil thoughts, for if you fail to do so, they will become ideas, if you do not, they will become desires, so fight against them. If you do not, they will become a form of determination and intention, if you do not resist, they will become actions, and if you do not follow them up with their opposite, they will become habits that will be hard to quit.

(Imam Ibn Al-Qayyim – Al-Fawa’Id – A Collection Of Wise Sayings pg 54.  )