觀無量壽佛經疏 4.17

4.17

又深心深信者，決定建立自心，順教修行，永除疑錯，不為一切別解別行、異學異見異執之所退失傾動也。

Furthermore, as for the deep faith of the deep mind, it means resolutely establishing one's own mind, cultivating in accordance with the teaching, forever eliminating doubt and error, and not being caused to regress or be shaken by any different understandings, different practices, heterodox studies, divergent views, or divergent attachments.