The records of the Ch'an sect, including the Transmission of the Lamp, and the collections of kung-ans, do not frequently refer to tso-ch'an practice. It was understood that by the time practitioners began to ts'an Ch'an, they already had a very good foundation in tso-ch'an. Such a basis is needed if one is to effectively practice kung-an and hua-t'ou. Beginners may get some usefulness out of the constant repetition, but this will be similar to chanting a mantra. Because the beginner lacks the ability to bring his mind to a deep quiescent state, it would be difficult, if not impossible to experience self-nature or become enlightened.

Throughout Ch'an history we read of advanced practitioners who visited masters in order to assess their own understanding of Ch'an, or certify their own attainment. These situations were well-suited for applying the methods of kung-an and hua-t'ou. It is important to remember that any interchange between master and disciple can be an opportunity for a live, spontaneous kung-an or hua-t'ou, and that these practices should not be thought of as being limited to the sayings and questions from the historical record.

Ta-hui Tsung-kao 大慧宗杲(1089-1163) was one of the greatest advocates of kung-an practice. From his record of sayings we see that he maintained that tso-ch'an was very necessary to settle the wandering mind, and bring about emergent samadhi. It is only then that the student can effectively use the kung-an or hua-t'ou. Even though kung-an and hua-t'ou practice can be done while walking, standing, or even lying down, its fundamental basis is still tso-ch'an.