釋氏要覽 2.144

2.144

涅盤經云。有一人渡海。假於浮囊。有一羅剎隨渡者乞其浮囊。乃至一針眼許。渡者不得。此喻持戒人。守護戒法。如渡海浮囊。不得少許穿漏。方渡生死大海。

The Nirvāṇa Sūtra says: 'A person was crossing the ocean by relying on a floating skin-raft. A rākṣasa followed the voyager and begged for his raft, even down to the amount of a needle-eye. The voyager did not give it. This is a metaphor for one who upholds the precepts: guarding and protecting the rules of discipline is like the floating raft used to cross the ocean; one must not allow the slightest puncture or leak, and only then can one cross over the great sea of birth and death.'