Faith, understanding, practice, and realization exist at different levels: the level of consciousness and the level of the mind-root. What ultimately and decisively plays the determining and sovereign role is faith, understanding, practice, and realization at the level of the mind-root.
If only the consciousness has faith, the mind-root cannot take action, one cannot diligently practice, and one cannot realize the Dharma. Only when the mind-root has faith is it true faith; if the mind-root lacks faith, one cannot truly begin the practice.
"Deep" refers to the mind-root; "shallow" refers to consciousness. "Earnest" refers to the mind-root; "not earnest" refers to consciousness. For example, only when the mind-root has deep faith and earnest vow towards the Pure Land can one be reborn there. If only the consciousness believes the Pure Land exists, but the mind-root does not believe, one cannot go. Whether one goes or not is determined by the mind-root.
Therefore, faith has levels of depth, and vows have levels of strength. Only what can be sovereign has strength; what cannot be sovereign lacks strength.
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