HOW SELF-ENQUIRY SHOULD BE PRACTISED: THE ANALOGY OF THE BESIEGED FORT
Bhagavan sometimes used the analogy of a besieged fort. If one systematically closes off all the entrances to a fort and then picks off the occupants one by one as they try to come out, sooner or later the fort will be empty. We should apply these same tactics to the mind. How to go about doing this? Seal off the entrances and exits to the mind by not reacting to rising thoughts or sense impressions. Don't let new ideas, judgements, likes, dislikes, etc. enter the mind, and don't let rising thoughts flourish and escape your attention. When you have sealed off the mind in this way, challenge each emerging thought as it appears by asking, 'Where have you come from?' or 'Who is the person who is having this thought?' If you can do this continuously, with full attention, new thoughts will appear momentarily and then disappear. If you can maintain the siege for long enough, a time will come when no more thoughts arise; or if they do, they will only be fleeting, undistracting images on the periphery of consciousness. In that thought-free state you will begin to experience yourself as consciousness, not as mind or body.
– Annamalai Swami. Self-realised student of Ramana Maharshi
Remember, to know Yourself, return to the silence before words.