“Within the household” means the whole family. In such a home, men and women are free of illness and pain, blessed with fortune and long life. All feel the auspicious power of concord; the elders live in peace and comfort, so they scarcely perceive that old age is drawing near.
None knows a disciple better than his teacher; none knows a son better than his father.
Here “disciple” refers to a student, and “teacher” to an instructor. Only a teacher truly understands a student’s temperament; only a father clearly knows his son’s inclinations.
I have seen those who serve as teachers never, apart from teaching book-learning, impart the wisdom of self-preservation.
The wisdom of self‑preservation means guarding one’s vital essence and not being ensnared by carnal desires. I have observed teachers who, apart from instructing their pupils in reading, fail to teach them to curb lust and protect their bodies. This is truly lamentable.
Some, because their pupils are clever, allow them to grow frivolous and unrestrained.
“Frivolous and unrestrained” describes impetuous youth: arrogant and conceited, still ridden with superficial impulses. Such students ought to be earnestly exhorted to cultivate gravity and steadiness. Yet because they are bright and quick‑witted, teachers indulge them instead of instructing, letting them act recklessly without restraint.
Some, yielding to the household head’s fond partiality, allow the youth to chase pleasure like butterflies and bees running wild.
The “household head” is the pupil’s parent. “Fond partiality” means shielding one’s child from reproach. Butterflies darting and bees swarming among blossoms are a metaphor for young men frequenting places of debauchery. Because parents dote on their sons, they permit such reckless lechery and refuse to discipline them in earnest.
When sensual desires first awaken, innate conscience fades little by little. “The opening of desire” is described as an aperture through which sensual desire arises.