I am going to say something that might be missed or not emphasized enough in many explanations of Shikantaza Zazen. (I apologize to any teachers who do in fact say this).
In Shikantaza, trains of thought and stormy emotions might come. and we are told to release the thoughts, become untangled, returning to the posture or breath or 'open awareness,' the stillness and silence free of thoughts. Then, when more thoughts come, we just repeat. That is correct.
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SIT-A-LONG with JUNDO: THOUGHTS and EMOTIONS are GOOD ZAZEN too! »