Merits and faults do not cancel each other out.

After performing the release of life (fishing of living beings), can the matter of birth-and-death in saṃsāra be changed? After slandering the Three Jewels, one will fall into hell upon death—can releasing life help one escape the karmic retribution of hell? If one owes someone ten thousand yuan, after releasing life, is the debt dissolved? After releasing life, can one attain realization of the fruits and see the mind and perceive self-nature (seeing the mind), and can one be reborn in the land of bliss (sukhāvatī)? For the sentient beings killed in past and present lives, will the karmic grudges thus be resolved?

A single wholesome act cannot substitute for all wholesome acts, much less can it substitute for pure conduct. Only pure conduct can make the mind pure, thereby eliminating the defiled mind and transforming the defiled karmic seeds; only then can karmic retribution truly be changed. Seeking nothing is pure conduct; being without greed, without anger, and without delusion is pure conduct; being free from ignorance is pure conduct. Of course, after releasing life and doing good deeds, one forms wholesome karmic connections with sentient beings and one's merit increases, which can support the advancement of precepts, meditation (samādhi), and wisdom (prajñā), and helps in realizing the fruits and seeing the mind. As merit increases, unwholesome karma may temporarily fail to manifest; one's karmic creditors, out of admiration for one's virtue, will no longer press for repayment of debts, and will no longer create obstacles, so studying the Dharma and cultivating the Path will go smoothly.