The mark of spiritual practice is the transformation of mental activities and mental factors (caitta)

The mental factors (caittas) of ordinary beings differ from one another as well, and it is best that one's mental factors before studying Buddhism and after studying Buddhism become more and more different. If someone has studied Buddhism for ten or twenty years, yet their mind-ground, mental conduct, and mental factors remain the same as before, then what has this person been doing all those decades? If after studying for many, many years, their mental conduct and mental factors have not changed at all, and their afflictions have not been subdued to a certain degree, so that the difference between their mental factors and mental conduct and those of a stream-enterer is still very great, how could they advance toward the path of stream-entry and then realize the first fruit? If the mind does not change, yet one claims a noble fruit, then one's virtue does not match one's position, and calamity is bound to follow.

As long as cultivation gives rise to the seven factors of enlightenment, the mental factors must change; if they do not change, the seven factors of enlightenment are not complete, and if the seven factors of enlightenment are not complete, one can never realize the fruit no matter what. How many people have not even come close to the seven factors of enlightenment, yet have obtained a great noble fruit and gone home to enjoy it—this is the Dharma-ending age.