Those who grasp at precepts not established by the Buddha, which cannot bring liberation, cannot be liberated from birth and death

Original text of the Laṅkāvatāra Sūtra: 大慧。戒取者云何。须陀洹不取戒。谓善见受生处苦相故。是故不取。大慧。取者谓愚夫。决定受习苦行。为众具乐。故求受生。彼则不取。除回向自觉胜。离妄想。无漏法相行方便。受持戒支。是名须陀洹取戒相断。

Explanation: The Buddha said, "Mahāmati, what does the grasping of precepts mean? A stream-enterer does not grasp at non-precepts, and does not hold precepts that cannot bring liberation. Because a stream-enterer is skilled in observing the marks of the suffering and retributive results of holding precepts that are not in accord with reason—which cannot liberate one from birth and death—therefore he does not grasp at non-precepts and does not hold precepts that are contrary to reason. Mahāmati, those who grasp at non-precepts not established by the Buddha that cannot bring liberation are foolish ordinary beings; they will surely accept and practice asceticism and carry out austerities, with the aim of obtaining the various worldly pleasures, and so they will undergo rebirth again."

A stream-enterer, however, will not grasp at non-precepts—unless he has turned his mind toward the path to buddhahood, has already departed from deluded views, and has eliminated afflictions in his mind-ground and reached the untainted state; then, as an expedient means to gather in and guide sentient beings, he may accord with conditions and manifest the appearance of holding the non-precepts of the non-Buddhist paths. This shows that a stream-enterer has eliminated the grasping of precepts.