By What Does Tathāgatagarbha Sustain and Transform the Rūpakāya?

The Tathāgatagarbha perpetually abides in quiescent extinction without movement. If it manifests any dharmas, it must be the result of the mental activity of the manas, and the manas must invariably serve as its concomitant condition. Superficially, when the Tathāgatagarbha forms the name-and-form fertilized ovum, transforms the fertilized ovum, and repairs the material body tissues, it may seem devoid of the manas' function. In reality, the function of the manas is always present. The manas perpetually corresponds with karmic seeds, and the Tathāgatagarbha accommodates karmic seeds—both meritorious and non-meritorious—which is equivalent to accommodating the manas. Most of the time, when the Tathāgatagarbha gives rise to mundane dharmas, it is based on karmic seeds. Even with the manas' continuous contemplation and decisions, when the Tathāgatagarbha cooperates with the manas, it must still rely on karmic seeds, meritorious causes and conditions, and other causal factors. 

If the causal conditions are unfavorable, merit is insufficient, there are no karmic seeds, or the karmic seeds have not yet ripened, the Tathāgatagarbha cannot give rise to dharmas according to the manas' decisions. For example, many people desire promotion, wealth, and superior mundane rewards, but lacking karmic seeds and with conditions unripe, they can only continue their former existence, leading an ordinary commoner's life. Another example: some are destined for the karmic retribution of frequent illness; no matter how hard they strive, nor how much money and effort they expend, they cannot repair their bodies to become healthy. Even the merit of an emperor is insufficient. Moreover, once an emperor exhausts his merit, he may commit suicide, be killed, or be overthrown by usurpers. In the world, many are born with great merit, but by indulging excessively and depleting this merit from childhood, upon growing up, when the merit is exhausted, they either die, live in poverty, or suffer numerous calamities. 

The retributions of the three realms follow the pull of karma; the Tāthāgatagarbha revolves according to karma. However, if the power of vows surpasses the power of karma, it can pull the Tathāgatagarbha to follow the vow. When ordinary beings make great vows, they gradually break free from the bonds of karma, transform fundamentally, become sages, and ultimately achieve Buddhahood. Therefore, repentance and vow-making constitute a powerful practice. As long as there is a vow, as long as the manas holds a vow, it will inevitably be fulfilled someday. No vow is empty; all will be realized—it is merely a matter of when the conditions mature. After these great vows are made, the Tathāgatagarbha records them. When the seeds ripen, the wish will be fulfilled. What we need to do is twofold: first, make pure, great, and wholesome vows; second, diligently strive to ripen the seeds of the vow-power. In the future, we will attain the fruition of the vow.